diff --git a/.env.example b/.env.example
index 7015999..52e7665 100644
--- a/.env.example
+++ b/.env.example
@@ -2,9 +2,26 @@
 ## signNow API SDK configuration
 ##
 
-## Replace these dummy values with your actual credentials except SIGNNOW_API_HOST
+# Required — replace placeholders with real credentials before running.
 SIGNNOW_API_HOST=https://api.signnow.com
-SIGNNOW_API_BASIC_TOKEN=test
-SIGNNOW_API_USERNAME=test
-SIGNNOW_API_PASSWORD=test
-SIGNNOW_DOWNLOADS_DIR=~/Downloads
+SIGNNOW_API_BASIC_TOKEN=<replace-me>
+SIGNNOW_API_USERNAME=<replace-me>
+SIGNNOW_API_PASSWORD=<replace-me>
+
+# Path inside the running environment where downloaded files are written.
+# Inside Docker, leave as /tmp (or another writable path). The ~ does not expand in containers.
+SIGNNOW_DOWNLOADS_DIR=/tmp
+
+##
+## Sample-app runtime configuration
+##
+
+# Public base URL used to build redirect URIs sent to the SignNow embed widget.
+# Must match the host the browser reaches this app on.
+APP_BASE_URL=http://localhost:8080
+
+# Demo-only signer credentials used by samples that generate limited signer tokens.
+# For production deployments replace with per-tenant values or remove the affected samples.
+SIGNNOW_DEMO_USER_EMAIL=example@example.com
+SIGNNOW_DEMO_USER_PASSWORD=example
+SIGNNOW_SIGNER_EMAIL=test@example.com
diff --git a/Dockerfile b/Dockerfile
index 89d56fd..2018677 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,10 +1,21 @@
-FROM maven:3.9.9-eclipse-temurin-23 AS build
+FROM maven:3.9.9-eclipse-temurin-17 AS build
 WORKDIR /app
 COPY pom.xml ./
+RUN mvn -B dependency:go-offline
 COPY src ./src
-RUN mvn clean install package -DskipTests
+RUN mvn -B clean package -DskipTests
 
-FROM openjdk:23-jdk-slim
-VOLUME /tmp
-COPY --from=build /app/target/java-sample-app-0.0.1-SNAPSHOT.jar app.jar
-ENTRYPOINT ["java", "-jar", "/app.jar"]
+FROM eclipse-temurin:17-jre
+RUN apt-get update \
+    && apt-get install -y --no-install-recommends curl \
+    && rm -rf /var/lib/apt/lists/* \
+    && groupadd -r app && useradd -r -g app -d /home/app -m app
+WORKDIR /home/app
+COPY --from=build /app/target/java-sample-app-0.0.1-SNAPSHOT.jar /home/app/app.jar
+RUN chown -R app:app /home/app
+USER app
+ENV JAVA_OPTS="-XX:MaxRAMPercentage=75 -XX:+UseG1GC"
+EXPOSE 8080
+HEALTHCHECK --interval=30s --timeout=3s --start-period=20s --retries=3 \
+    CMD curl -fsS http://127.0.0.1:8080/actuator/health || exit 1
+ENTRYPOINT ["sh", "-c", "exec java $JAVA_OPTS -jar /home/app/app.jar"]
diff --git a/LICENSE.md b/LICENSE.md
new file mode 100644
index 0000000..dd4e228
--- /dev/null
+++ b/LICENSE.md
@@ -0,0 +1,21 @@
+# The MIT License
+
+Copyright (c) 2003-present SignNow
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
diff --git a/README.md b/README.md
index ad8c45f..31e3dd2 100644
--- a/README.md
+++ b/README.md
@@ -1,93 +1,197 @@
-# SignNow Java SDK Sample Application
+# SignNow Java Sample App
 
-This is a demonstration project that showcases how to use the [SignNow Java SDK](https://github.com/signnow/SNJavaSDK) to interact with the SignNow API.
+[![Java](https://img.shields.io/badge/java-17-orange)](https://openjdk.org/)
+[![Spring Boot](https://img.shields.io/badge/Spring_Boot-3.4-brightgreen)](https://spring.io/projects/spring-boot)
+[![SignNow SDK](https://img.shields.io/badge/SignNow_SDK-3.5+-light)](https://github.com/signnow/SNJavaSDK)
+[![License](https://img.shields.io/badge/license-MIT-green)](./LICENSE)
 
-Each sample represents a standalone use case and is implemented in a separate directory under:
+A Spring Boot application demonstrating the SignNow API via the official [SignNow Java SDK](https://github.com/signnow/SNJavaSDK).
 
-```
-src/main/java/com/signnow/samples
-```
+## Quick Start
 
-The static frontend resources for each sample (e.g. HTML, JS, CSS) are located in:
+### 1. Enter the directory
 
-```
-src/main/resources/static/samples
+```bash
+cd SampleApps/java-sample-app
 ```
 
-## Getting Started
-
-### 1. Set Up Your Environment
-
-Copy the provided `.env.example` file to `.env`:
+### 2. Configure environment
 
 ```bash
 cp .env.example .env
 ```
 
-Edit the `.env` file and replace the placeholder values with your actual SignNow API credentials and settings.
+Edit `.env` and fill in your SignNow credentials:
 
-### 2. Build and Run the Application
+| Variable | Example | Description |
+|---|---|---|
+| `SIGNNOW_API_HOST` | `https://api.signnow.com` | Production or sandbox URL |
+| `SIGNNOW_API_BASIC_TOKEN` | `c2lnbk5vdy4...` | Base64 token from [API Dashboard](https://app.signnow.com/webapp/api-dashboard/keys) |
+| `SIGNNOW_API_USERNAME` | `you@example.com` | Your SignNow account email |
+| `SIGNNOW_API_PASSWORD` | `••••••` | Your SignNow account password |
+| `SIGNNOW_DOWNLOADS_DIR` | `/tmp/signnow-downloads` | Where downloaded documents are cached |
+| `APP_BASE_URL` | `http://localhost:8080` | Public base URL used in `redirect_uri` |
+| `SIGNNOW_SIGNER_EMAIL` | `signer@example.com` | Default embedded signer email |
+| `SIGNNOW_DEMO_USER_EMAIL` | `demo@example.com` | Demo sender email (used in some samples) |
+| `SIGNNOW_DEMO_USER_PASSWORD` | `••••••` | Demo sender password |
 
-You can build and run the application using Docker:
+### 3. Run with Docker
 
 ```bash
 docker build -t java-sample-app .
 docker run -v $(pwd)/.env:/.env -p 8080:8080 java-sample-app
 ```
 
-Once the app is running, access it via:
+### 4. Run locally (no Docker)
 
-```
-http://localhost:8080/samples/{exampleName}
+```bash
+mvn spring-boot:run
 ```
 
-Replace `{exampleName}` with the name of the specific example you want to run (e.g. `DocumentInvite`, `PrefillForm`, etc.).
+Requires Java 17+ and Maven 3.9+ on `PATH`. The app reads `.env` from the working directory.
 
-## Routing Logic
+### 5. Open a sample
 
-All requests are routed through a single controller: `RoutingController`.
+```
+http://localhost:8080/samples/EmbeddedSignerConsentForm
+```
 
-* **GET /samples/{exampleName}**: Loads and executes the corresponding `IndexController` class from the example folder.
-* **POST /api/samples/{exampleName}**: Handles form submissions for the given example.
+`http://localhost:8080/samples` lists all available samples.
+
+## Available Samples (20)
+
+| Sample | Description |
+|---|---|
+| EmbeddedSignerConsentForm | Consent form with single embedded signer |
+| EmbeddedSenderWithoutFormFile | Sales proposal — embedded sender |
+| EmbeddedSenderWithFormCreditLoanAgreement | Credit loan agreement |
+| EmbeddedSignerConsumerServices | Veterinary intake form |
+| EmbeddedSignerPatientIntakeForm | Patient intake (healthcare) |
+| EmbeddedSignerWithFormInsurance | Insurance claim form |
+| MedicalInsuranceClaimForm | Medical insurance claim |
+| EmbeddedEditingAndSigningDG | Document generation: edit + sign |
+| EmbeddedSenderWithFormAndFirstSigner | Sender is also first signer |
+| EmbeddedSenderWithFormDG | Document generation variant |
+| EmbeddedSenderWithFormDGAdjunct | DG adjunct form |
+| EmbeddedSenderWithFormDGConstr | DG construction form |
+| ISVWithFormAndOneClickSendBasicPrefill | ISV one-click send, basic prefill |
+| ISVWithFormAndOneClickSendMergeFields | ISV one-click send, merge fields |
+| HROnboardingSystem | HR onboarding multi-document flow |
+| UploadEmbeddedSender | Upload PDF + embedded sender |
+| PrefillAndEmbeddedSendingAgreement | Prefill + embedded send |
+| PrefillAndOneClickSendingAgreement | Prefill + one-click send |
+| EVDemoSendingAnd3EmbeddedSigners | Real estate: 3 sequential embedded signers |
+| UploadEmbeddedEditingAndInvite | Upload PDF, embedded edit, invite |
+
+## Project Structure
 
-Only example names matching `^[a-zA-Z0-9_]+$` are allowed for security reasons.
+```
+src/main/java/com/signnow/
+  javasampleapp/
+    JavaSampleAppApplication.java   Spring Boot entry point
+    ExampleInterface.java           Sample contract (handleGet + handlePost)
+    controllers/
+      RoutingController.java        GET /samples/:name, POST /api/samples/:name
+    config/
+      AppConfig.java                Reads .env; provides AppConfig.sampleUrl()
+  samples/
+    <SampleName>/
+      IndexController.java          Implements ExampleInterface
+
+src/main/resources/
+  static/
+    samples/<SampleName>/
+      index.html                    UI served on GET /samples/<SampleName>
+    css/, img/                      Shared static assets
+  application.properties            Spring config
+
+src/test/
+  JavaSampleAppApplicationTests.java  Context load test
+  controllers/RoutingControllerTest.java  MockMvc routing tests
+```
 
-## Structure of a Sample Example
+## Routing
+
+| Method | Path | Handler |
+|---|---|---|
+| GET | `/samples/{name}` | `samples/<name>/IndexController.handleGet` |
+| POST | `/api/samples/{name}` | `samples/<name>/IndexController.handlePost` |
+| GET | `/css/*`, `/img/*`, etc. | Shared static files |
+
+Sample names must match `^[a-zA-Z0-9_]+$`. `RoutingController` loads each sample's `IndexController` by class name convention at request time — no whitelist or registration needed.
+
+## Add a New Sample
+
+1. Create `src/main/java/com/signnow/samples/MyNewSample/IndexController.java`:
+   ```java
+   package com.signnow.samples.MyNewSample;
+
+   import com.signnow.javasampleapp.ExampleInterface;
+   import org.springframework.http.ResponseEntity;
+   import org.springframework.stereotype.Controller;
+   import java.io.IOException;
+   import java.util.Map;
+
+   @Controller
+   public class IndexController implements ExampleInterface {
+       @Override
+       public ResponseEntity<String> handleGet(Map<String, String> queryParams) throws IOException {
+           try (var in = getClass().getResourceAsStream("/static/samples/MyNewSample/index.html")) {
+               return ResponseEntity.ok().header("Content-Type", "text/html")
+                       .body(new String(in.readAllBytes()));
+           }
+       }
+
+       @Override
+       public ResponseEntity<?> handlePost(String formData) throws Exception {
+           // parse formData as JSON and implement your logic
+           return ResponseEntity.ok("{}");
+       }
+   }
+   ```
+2. Create `src/main/resources/static/samples/MyNewSample/index.html`.
+3. Restart the application — `RoutingController` discovers the new controller automatically.
+
+## Tests
 
-Each sample should implement the `ExampleInterface` and provide its own `IndexController` class with `handleGet()` and `handlePost()` methods.
+```bash
+mvn test
+```
 
-____
+2 test classes:
+- `JavaSampleAppApplicationTests` — Spring context loads without errors
+- `RoutingControllerTest` — 6 MockMvc tests covering name validation (`^[a-zA-Z0-9_]+$`), 404 for unknown samples, and routing dispatch
 
-## Ready to build eSignature integrations with SignNow API? Get the SignNow extension for GitHub Copilot
+Tests do **not** exercise real SignNow API calls (live credentials required).
 
-Use AI-powered code suggestions to generate SignNow API code snippets in your IDE with GitHub Copilot. Get examples for common integration tasks—from authentication and sending documents for signature to handling webhooks, and building branded workflows.
+## SDK Notes
 
-###  **🚀 Why use SignNow with GitHub Copilot**
+Known constraints in the SignNow Java SDK that affect this codebase:
 
-* **Relevant code suggestions**: Get AI-powered, up-to-date code snippets for SignNow API calls. All examples reflect the latest API capabilities and follow current best practices.
-* **Faster development**: Reduce time spent searching documentation.
-* **Fewer mistakes**: Get context-aware guidance aligned with the SignNow API.
-* **Smooth onboarding**: Useful for both new and experienced developers working with the API.
+**No multipart support in `RoutingController`** — `handlePost` receives `@RequestBody String formData` (raw JSON), not multipart. Samples that conceptually "upload" a file instead read a pre-bundled PDF from `src/main/resources/static/samples/<Name>/`. See `UploadEmbeddedSender` for the pattern.
 
-### **Prerequisites:**
+**`Invite` constructor order** — `new Invite(email, roleId, order, firstName, lastName)`. There is no shorter overload; all five parameters are required.
 
-1\. GitHub Copilot installed and enabled.  
-2\. SignNow account. [Register here](https://www.signnow.com/developers)
+**`DocumentInvitePostResponse.getData()`** — Returns a collection; each item exposes `.getRoleId()` (to match against role IDs you looked up) and `.getId()` (the invite ID needed for `DocumentInviteLinkPostRequest`).
 
-### ⚙️ **How to use it**
+**`DocumentInviteLinkPostRequest` constructor** — `(authType, linkExpiration)` where `authType` is typically `"none"`. Chain `.withDocumentId()` and `.withFieldInviteId()` before sending.
 
-1\. Install the [SignNow extension](https://github.com/apps/signnow).
+**`DocumentEmbeddedEditorLinkPostRequest` constructor** — `(redirectUri, redirectTarget, linkExpiration)`. Chain `.withDocumentId()` before sending. Response: `getData().getUrl()`.
 
-2\. Start your prompts with [@signnow](https://github.com/signnow) in the Copilot chat window. The first time you use the extension, you may need to authorize it.
+## Tech Stack
 
-3\. Enter a prompt describing the integration scenario.   
-Example: @signnow Generate a Java code example for sending a document group to two signers.
+- Java 17
+- Spring Boot 3.4.1
+- `signnow-java-sdk` 3.5.1 (from Maven Central)
+- Maven 3.9
+- JUnit 5 + Spring MockMvc (tests)
+- Docker: multi-stage `maven:3.9-eclipse-temurin-17` → `eclipse-temurin:17-jre`
 
-4\. Modify the generated code to match your app’s requirements—adjust parameters, headers, and workflows as needed.
+## GitHub Copilot Extension
 
-### **Troubleshooting**
-**The extension doesn’t provide code examples for the SignNow API**
+Get AI-powered SignNow code suggestions in your IDE:
+[github.com/apps/signnow](https://github.com/apps/signnow) — start prompts with `@signnow`.
 
-Make sure you're using `@signnow` in the Copilot chat and that the extension is installed and authorized.
+## License
 
-____
+See [LICENSE](./LICENSE).
diff --git a/pom.xml b/pom.xml
index 73260f4..776aa61 100644
--- a/pom.xml
+++ b/pom.xml
@@ -34,6 +34,10 @@
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-web</artifactId>
         </dependency>
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-actuator</artifactId>
+        </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>
             <artifactId>spring-boot-starter-test</artifactId>
@@ -42,7 +46,7 @@
         <dependency>
             <groupId>com.signnow</groupId>
             <artifactId>signnow-java-sdk</artifactId>
-            <version>3.5.0</version>
+            <version>3.5.1</version>
         </dependency>
     </dependencies>
 
diff --git a/src/main/java/com/signnow/javasampleapp/config/AppConfig.java b/src/main/java/com/signnow/javasampleapp/config/AppConfig.java
new file mode 100644
index 0000000..12dcd1f
--- /dev/null
+++ b/src/main/java/com/signnow/javasampleapp/config/AppConfig.java
@@ -0,0 +1,57 @@
+package com.signnow.javasampleapp.config;
+
+import jakarta.annotation.PostConstruct;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.stereotype.Component;
+
+/**
+ * Runtime config holder for sample controllers that are instantiated via reflection
+ * and cannot receive Spring-injected dependencies. Spring populates the static fields
+ * at startup through {@link Holder}; controllers read them via the static accessors.
+ */
+public final class AppConfig {
+
+    private AppConfig() {}
+
+    private static volatile String baseUrl = "http://localhost:8080";
+    private static volatile String demoUserEmail = "example@example.com";
+    private static volatile String demoUserPassword = "example";
+
+    public static String baseUrl() {
+        return baseUrl;
+    }
+
+    public static String sampleUrl(String exampleName) {
+        return baseUrl + "/samples/" + exampleName;
+    }
+
+    public static String demoUserEmail() {
+        return demoUserEmail;
+    }
+
+    public static String demoUserPassword() {
+        return demoUserPassword;
+    }
+
+    @Component
+    static class Holder {
+
+        Holder(@Value("${app.base-url:http://localhost:8080}") String baseUrl,
+               @Value("${signnow.api.demo_user_email:example@example.com}") String demoUserEmail,
+               @Value("${signnow.api.demo_user_password:example}") String demoUserPassword) {
+            AppConfig.baseUrl = trimTrailingSlash(baseUrl);
+            AppConfig.demoUserEmail = demoUserEmail;
+            AppConfig.demoUserPassword = demoUserPassword;
+        }
+
+        @PostConstruct
+        void ready() {
+            // Touch volatile fields to publish writes; initialization happens in the constructor.
+        }
+
+        private static String trimTrailingSlash(String url) {
+            if (url == null || url.isEmpty()) return url;
+            return url.endsWith("/") ? url.substring(0, url.length() - 1) : url;
+        }
+    }
+}
diff --git a/src/main/java/com/signnow/javasampleapp/config/SecurityHeadersFilter.java b/src/main/java/com/signnow/javasampleapp/config/SecurityHeadersFilter.java
new file mode 100644
index 0000000..26b039b
--- /dev/null
+++ b/src/main/java/com/signnow/javasampleapp/config/SecurityHeadersFilter.java
@@ -0,0 +1,31 @@
+package com.signnow.javasampleapp.config;
+
+import jakarta.servlet.FilterChain;
+import jakarta.servlet.ServletException;
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+import org.springframework.core.Ordered;
+import org.springframework.core.annotation.Order;
+import org.springframework.stereotype.Component;
+import org.springframework.web.filter.OncePerRequestFilter;
+
+import java.io.IOException;
+
+@Component
+@Order(Ordered.HIGHEST_PRECEDENCE)
+public class SecurityHeadersFilter extends OncePerRequestFilter {
+
+    @Override
+    protected void doFilterInternal(HttpServletRequest request,
+                                    HttpServletResponse response,
+                                    FilterChain filterChain) throws ServletException, IOException {
+        response.setHeader("X-Content-Type-Options", "nosniff");
+        response.setHeader("X-Frame-Options", "SAMEORIGIN");
+        response.setHeader("Referrer-Policy", "strict-origin-when-cross-origin");
+        response.setHeader("Permissions-Policy", "geolocation=(), microphone=(), camera=()");
+        if (request.isSecure()) {
+            response.setHeader("Strict-Transport-Security", "max-age=31536000; includeSubDomains");
+        }
+        filterChain.doFilter(request, response);
+    }
+}
diff --git a/src/main/java/com/signnow/javasampleapp/controllers/GlobalExceptionHandler.java b/src/main/java/com/signnow/javasampleapp/controllers/GlobalExceptionHandler.java
new file mode 100644
index 0000000..306ec6e
--- /dev/null
+++ b/src/main/java/com/signnow/javasampleapp/controllers/GlobalExceptionHandler.java
@@ -0,0 +1,55 @@
+package com.signnow.javasampleapp.controllers;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.signnow.core.exception.SignNowApiException;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.ResponseEntity;
+import org.springframework.http.converter.HttpMessageNotReadableException;
+import org.springframework.web.bind.annotation.ControllerAdvice;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+
+import java.util.LinkedHashMap;
+import java.util.Map;
+
+@ControllerAdvice
+public class GlobalExceptionHandler {
+
+    private static final Logger log = LoggerFactory.getLogger(GlobalExceptionHandler.class);
+
+    @ExceptionHandler(HttpMessageNotReadableException.class)
+    public ResponseEntity<Map<String, Object>> handleMalformedBody(HttpMessageNotReadableException e) {
+        log.warn("Malformed request body: {}", e.getMostSpecificCause().getMessage());
+        return problem(HttpStatus.BAD_REQUEST, "Malformed request body");
+    }
+
+    @ExceptionHandler({JsonProcessingException.class, IllegalArgumentException.class, ClassCastException.class})
+    public ResponseEntity<Map<String, Object>> handleBadInput(Exception e) {
+        log.warn("Rejected request due to invalid input: {}", e.getMessage());
+        return problem(HttpStatus.BAD_REQUEST, "Invalid request payload");
+    }
+
+    @ExceptionHandler(SignNowApiException.class)
+    public ResponseEntity<Map<String, Object>> handleSignNowApi(SignNowApiException e) {
+        log.error("SignNow API call failed", e);
+        return problem(HttpStatus.BAD_GATEWAY, "Upstream SignNow API error");
+    }
+
+    @ExceptionHandler(Exception.class)
+    public ResponseEntity<Map<String, Object>> handleUnexpected(Exception e) {
+        log.error("Unhandled exception", e);
+        return problem(HttpStatus.INTERNAL_SERVER_ERROR, "Internal server error");
+    }
+
+    private ResponseEntity<Map<String, Object>> problem(HttpStatus status, String message) {
+        Map<String, Object> body = new LinkedHashMap<>();
+        body.put("success", false);
+        body.put("status", status.value());
+        body.put("message", message);
+        return ResponseEntity.status(status)
+                .contentType(MediaType.APPLICATION_JSON)
+                .body(body);
+    }
+}
diff --git a/src/main/java/com/signnow/javasampleapp/controllers/RoutingController.java b/src/main/java/com/signnow/javasampleapp/controllers/RoutingController.java
index e6475d1..5414b62 100644
--- a/src/main/java/com/signnow/javasampleapp/controllers/RoutingController.java
+++ b/src/main/java/com/signnow/javasampleapp/controllers/RoutingController.java
@@ -1,7 +1,11 @@
 package com.signnow.javasampleapp.controllers;
 
 import com.fasterxml.jackson.databind.ObjectMapper;
+import com.signnow.core.exception.SignNowApiException;
 import com.signnow.javasampleapp.ExampleInterface;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.http.MediaType;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.*;
@@ -9,107 +13,91 @@
 import java.io.IOException;
 import java.util.HashMap;
 import java.util.Map;
+import java.util.regex.Pattern;
 
 @Controller
 public class RoutingController {
 
+    private static final Logger log = LoggerFactory.getLogger(RoutingController.class);
+
+    private static final Pattern EXAMPLE_NAME_PATTERN = Pattern.compile("^[a-zA-Z0-9_]+$");
+    private static final String CONTROLLER_PACKAGE = "com.signnow.samples.";
+    private static final String CONTROLLER_CLASS = ".IndexController";
+    private static final String FALLBACK_ERROR_HTML =
+            "<html><body><h1>404 - Page Not Found</h1></body></html>";
+
     @GetMapping("/")
     public ResponseEntity<String> root() throws IOException {
-        try (var inputStream = getClass().getResourceAsStream("/static/error.html")) {
-            if (inputStream == null) {
-                return ResponseEntity.status(404)
-                        .header("Content-Type", "text/html")
-                        .body("<html><body><h1>404 - Page Not Found</h1></body></html>");
-            }
-            String html = new String(inputStream.readAllBytes());
-            return ResponseEntity.status(404)
-                    .header("Content-Type", "text/html")
-                    .body(html);
-        }
+        return notFound();
     }
 
     @GetMapping("/samples/{exampleName}")
     public ResponseEntity<String> routeExample(
             @PathVariable String exampleName,
             @RequestParam Map<String, String> queryParams
-    ) throws IOException {
-        if (!exampleName.matches("^[a-zA-Z0-9_]+$")) {
-            try (var inputStream = getClass().getResourceAsStream("/static/error.html")) {
-                if (inputStream == null) {
-                    return ResponseEntity.status(404)
-                            .header("Content-Type", "text/html")
-                            .body("<html><body><h1>404 - Page Not Found</h1></body></html>");
-                }
-                String html = new String(inputStream.readAllBytes());
-                return ResponseEntity.status(404)
-                        .header("Content-Type", "text/html")
-                        .body(html);
-            }
+    ) throws IOException, SignNowApiException {
+        if (!EXAMPLE_NAME_PATTERN.matcher(exampleName).matches()) {
+            log.warn("Rejected sample GET with invalid name: {}", exampleName);
+            return notFound();
         }
-        String controllerPath = "com.signnow.samples." + exampleName + ".IndexController";
         try {
-            Class<?> controllerClass = Class.forName(controllerPath);
-            Object controllerInstance = controllerClass.getDeclaredConstructor().newInstance();
-            if (controllerInstance instanceof ExampleInterface) {
-                return ((ExampleInterface) controllerInstance).handleGet(queryParams);
+            ExampleInterface controller = loadExampleController(exampleName);
+            if (controller != null) {
+                return controller.handleGet(queryParams);
             }
+        } catch (ReflectiveOperationException e) {
+            log.error("Failed to instantiate example controller '{}'", exampleName, e);
         } catch (Exception e) {
-            // Log the error
-            System.err.println("Error loading example controller: " + e.getMessage());
-        }
-        try (var inputStream = getClass().getResourceAsStream("/static/error.html")) {
-            if (inputStream == null) {
-                return ResponseEntity.status(404)
-                        .header("Content-Type", "text/html")
-                        .body("<html><body><h1>404 - Page Not Found</h1></body></html>");
-            }
-            String html = new String(inputStream.readAllBytes());
-            return ResponseEntity.status(404)
-                    .header("Content-Type", "text/html")
-                    .body(html);
+            log.error("Example '{}' failed to handle GET", exampleName, e);
+            throw e;
         }
+        return notFound();
     }
 
     @PostMapping("/api/samples/{exampleName}")
     public ResponseEntity<?> handleFormSubmission(
             @PathVariable String exampleName,
-            @RequestBody String formData) throws IOException {
-        if (!exampleName.matches("^[a-zA-Z0-9_]+$")) {
-            try (var inputStream = getClass().getResourceAsStream("/static/error.html")) {
-                if (inputStream == null) {
-                    return ResponseEntity.status(404)
-                            .header("Content-Type", "text/html")
-                            .body("<html><body><h1>404 - Page Not Found</h1></body></html>");
-                }
-                String html = new String(inputStream.readAllBytes());
-                return ResponseEntity.status(404)
-                        .header("Content-Type", "text/html")
-                        .body(html);
-            }
+            @RequestBody String formData) throws IOException, SignNowApiException {
+        if (!EXAMPLE_NAME_PATTERN.matcher(exampleName).matches()) {
+            log.warn("Rejected sample POST with invalid name: {}", exampleName);
+            return notFound();
         }
-        String controllerPath = "com.signnow.samples." + exampleName + ".IndexController";
         try {
-            Class<?> controllerClass = Class.forName(controllerPath);
-            Object controllerInstance = controllerClass.getDeclaredConstructor().newInstance();
-            if (controllerInstance instanceof ExampleInterface) {
-                return ((ExampleInterface) controllerInstance).handlePost(formData);
+            ExampleInterface controller = loadExampleController(exampleName);
+            if (controller != null) {
+                return controller.handlePost(formData);
             }
-        } catch (Exception e) {
+        } catch (ReflectiveOperationException e) {
+            log.error("Failed to instantiate example controller '{}'", exampleName, e);
             Map<String, String> errorResponse = new HashMap<>();
-            errorResponse.put("error", e.getMessage());
+            errorResponse.put("error", "Example not available");
             return ResponseEntity.status(500)
-                    .header("Content-Type", "application/json")
+                    .contentType(MediaType.APPLICATION_JSON)
                     .body(new ObjectMapper().writeValueAsString(errorResponse));
+        } catch (Exception e) {
+            log.error("Example '{}' failed to handle POST", exampleName, e);
+            throw e;
         }
+        return notFound();
+    }
+
+    private ExampleInterface loadExampleController(String exampleName) throws ReflectiveOperationException {
+        String controllerPath = CONTROLLER_PACKAGE + exampleName + CONTROLLER_CLASS;
+        Class<?> controllerClass = Class.forName(controllerPath);
+        Object controllerInstance = controllerClass.getDeclaredConstructor().newInstance();
+        if (controllerInstance instanceof ExampleInterface example) {
+            return example;
+        }
+        return null;
+    }
+
+    private ResponseEntity<String> notFound() throws IOException {
         try (var inputStream = getClass().getResourceAsStream("/static/error.html")) {
-            if (inputStream == null) {
-                return ResponseEntity.status(404)
-                        .header("Content-Type", "text/html")
-                        .body("<html><body><h1>404 - Page Not Found</h1></body></html>");
-            }
-            String html = new String(inputStream.readAllBytes());
+            String html = inputStream == null
+                    ? FALLBACK_ERROR_HTML
+                    : new String(inputStream.readAllBytes());
             return ResponseEntity.status(404)
-                    .header("Content-Type", "text/html")
+                    .contentType(MediaType.TEXT_HTML)
                     .body(html);
         }
     }
diff --git a/src/main/java/com/signnow/samples/EVDemoSendingAnd3EmbeddedSigners/IndexController.java b/src/main/java/com/signnow/samples/EVDemoSendingAnd3EmbeddedSigners/IndexController.java
new file mode 100644
index 0000000..b394649
--- /dev/null
+++ b/src/main/java/com/signnow/samples/EVDemoSendingAnd3EmbeddedSigners/IndexController.java
@@ -0,0 +1,243 @@
+package com.signnow.samples.EVDemoSendingAnd3EmbeddedSigners;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.signnow.Sdk;
+import com.signnow.api.document.request.DocumentDownloadGetRequest;
+import com.signnow.api.document.response.DocumentDownloadGetResponse;
+import com.signnow.api.document.request.DocumentGetRequest;
+import com.signnow.api.document.response.DocumentGetResponse;
+import com.signnow.api.documentfield.request.DocumentPrefillPutRequest;
+import com.signnow.api.documentfield.request.data.Field;
+import com.signnow.api.documentfield.request.data.FieldCollection;
+import com.signnow.api.embeddedinvite.request.DocumentInviteLinkPostRequest;
+import com.signnow.api.embeddedinvite.request.DocumentInvitePostRequest;
+import com.signnow.api.embeddedinvite.request.data.Invite;
+import com.signnow.api.embeddedinvite.request.data.InviteCollection;
+import com.signnow.api.embeddedinvite.response.DocumentInviteLinkPostResponse;
+import com.signnow.api.embeddedinvite.response.DocumentInvitePostResponse;
+import com.signnow.api.template.request.CloneTemplatePostRequest;
+import com.signnow.api.template.response.CloneTemplatePostResponse;
+import com.signnow.core.ApiClient;
+import com.signnow.core.exception.SignNowApiException;
+import com.signnow.javasampleapp.ExampleInterface;
+import com.signnow.javasampleapp.config.AppConfig;
+import org.springframework.http.ResponseEntity;
+import org.springframework.stereotype.Controller;
+
+import java.io.File;
+import java.io.IOException;
+import java.net.URLEncoder;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.util.HashMap;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+
+@Controller
+public class IndexController implements ExampleInterface {
+
+    private static final String TEMPLATE_ID = "34009a3d21b5468d86d886cd715658c453335c61";
+    private static final String SAMPLE_NAME = "EVDemoSendingAnd3EmbeddedSigners";
+
+    @Override
+    public ResponseEntity<String> handleGet(Map<String, String> queryParams) throws IOException {
+        try (var inputStream = getClass().getResourceAsStream("/static/samples/" + SAMPLE_NAME + "/index.html")) {
+            if (inputStream == null) {
+                throw new IOException("HTML file not found in classpath");
+            }
+            String html = new String(inputStream.readAllBytes());
+            return ResponseEntity.ok().header("Content-Type", "text/html").body(html);
+        }
+    }
+
+    @Override
+    public ResponseEntity<?> handlePost(String formData) throws IOException, SignNowApiException {
+        Map<String, Object> data = new ObjectMapper().readValue(formData, Map.class);
+        String action = (String) data.getOrDefault("action", "");
+
+        ApiClient client = new Sdk().build().authenticate().getApiClient();
+
+        switch (action) {
+            case "start-workflow":
+                return startWorkflow(client, data);
+            case "next-signer":
+                return nextSigner(client, data);
+            case "download":
+                return download(client, data);
+            case "invite-status":
+                return inviteStatus(client, data);
+            default:
+                Map<String, Object> error = new HashMap<>();
+                error.put("error", "Invalid action");
+                return ResponseEntity.badRequest().body(new ObjectMapper().writeValueAsString(error));
+        }
+    }
+
+    private ResponseEntity<?> startWorkflow(ApiClient client, Map<String, Object> data) throws SignNowApiException, IOException {
+        String agentName   = (String) data.getOrDefault("agent_name", "");
+        String agentEmail  = (String) data.getOrDefault("agent_email", "");
+        String signer1Name  = (String) data.getOrDefault("signer1_name", "");
+        String signer1Email = (String) data.getOrDefault("signer1_email", "");
+        String signer2Name  = (String) data.getOrDefault("signer2_name", "");
+        String signer2Email = (String) data.getOrDefault("signer2_email", "");
+
+        // 1. Clone template
+        CloneTemplatePostRequest cloneReq = new CloneTemplatePostRequest();
+        cloneReq.withTemplateId(TEMPLATE_ID);
+        CloneTemplatePostResponse cloneResp = (CloneTemplatePostResponse) client.send(cloneReq).getResponse();
+        String documentId = cloneResp.getId();
+
+        // 2. Prefill signer name fields
+        FieldCollection fields = new FieldCollection();
+        if (!signer1Name.isEmpty()) {
+            fields.add(new Field("Signer 1 Name", signer1Name));
+            fields.add(new Field("Text Field 18", signer1Name));
+        }
+        if (!signer2Name.isEmpty()) {
+            fields.add(new Field("Signer 2 Name", signer2Name));
+            fields.add(new Field("Text Field 19", signer2Name));
+        }
+        DocumentPrefillPutRequest prefillReq = new DocumentPrefillPutRequest(fields);
+        prefillReq.withDocumentId(documentId);
+        client.send(prefillReq);
+
+        // 3. Get role IDs
+        String agentRoleId   = getRoleId(client, documentId, "Contract Preparer");
+        String signer1RoleId = getRoleId(client, documentId, "Recipient 1");
+        String signer2RoleId = getRoleId(client, documentId, "Recipient 2");
+
+        // 4. Create embedded invites for all three roles
+        InviteCollection invites = new InviteCollection();
+        invites.add(new Invite(agentEmail,   agentRoleId,   1, firstName(agentName),   lastName(agentName)));
+        invites.add(new Invite(signer1Email, signer1RoleId, 2, firstName(signer1Name), lastName(signer1Name)));
+        invites.add(new Invite(signer2Email, signer2RoleId, 3, firstName(signer2Name), lastName(signer2Name)));
+
+        DocumentInvitePostRequest inviteReq = new DocumentInvitePostRequest(invites, null);
+        inviteReq.withDocumentId(documentId);
+        DocumentInvitePostResponse inviteResp = (DocumentInvitePostResponse) client.send(inviteReq).getResponse();
+
+        // 5. Build roleId → inviteId map
+        Map<String, String> inviteMap = new HashMap<>();
+        for (var item : inviteResp.getData()) {
+            inviteMap.put(item.getRoleId(), item.getId());
+        }
+
+        // 6. Get invite link for agent (first signer)
+        String agentInviteId = inviteMap.get(agentRoleId);
+        String redirectUrl = makeRedirectUrl(documentId, "signer1");
+        String agentLink = getInviteLink(client, documentId, agentInviteId, redirectUrl);
+
+        Map<String, Object> result = new HashMap<>();
+        result.put("document_id", documentId);
+        result.put("embedded_link", agentLink);
+        result.put("message", "Agent embedded signing link created. Agent can now sign.");
+        return ResponseEntity.ok().header("Content-Type", "application/json")
+                .body(new ObjectMapper().writeValueAsString(result));
+    }
+
+    private ResponseEntity<?> nextSigner(ApiClient client, Map<String, Object> data) throws SignNowApiException, IOException {
+        String documentId = (String) data.get("document_id");
+        String roleName   = (String) data.get("roleName");
+        String redirectKey = "Recipient 1".equals(roleName) ? "signer2" : "finish";
+
+        String inviteId = getInviteIdForRoleName(client, documentId, roleName);
+        String signingLink = getInviteLink(client, documentId, inviteId, makeRedirectUrl(documentId, redirectKey));
+
+        Map<String, Object> result = new HashMap<>();
+        result.put("embedded_link", signingLink);
+        result.put("message", "Embedded link for " + roleName + " created. Ready for signing.");
+        return ResponseEntity.ok().header("Content-Type", "application/json")
+                .body(new ObjectMapper().writeValueAsString(result));
+    }
+
+    private ResponseEntity<?> download(ApiClient client, Map<String, Object> data) throws SignNowApiException, IOException {
+        String documentId = (String) data.get("document_id");
+        File file = downloadDocument(client, documentId);
+        String filename = file.getName();
+        byte[] content = Files.readAllBytes(file.toPath());
+        file.delete();
+        return ResponseEntity.ok()
+                .header("Content-Type", "application/pdf")
+                .header("Content-Disposition", "attachment; filename=\"" + filename + "\"")
+                .body(content);
+    }
+
+    private ResponseEntity<?> inviteStatus(ApiClient client, Map<String, Object> data) throws SignNowApiException, IOException {
+        String documentId = (String) data.get("document_id");
+
+        DocumentGetRequest docReq = new DocumentGetRequest();
+        docReq.withDocumentId(documentId);
+        DocumentGetResponse docResp = (DocumentGetResponse) client.send(docReq).getResponse();
+
+        List<Map<String, Object>> statuses = new LinkedList<>();
+        for (var invite : docResp.getFieldInvites()) {
+            Map<String, Object> entry = new HashMap<>();
+            entry.put("email", invite.getEmail());
+            entry.put("status", invite.getStatus());
+            entry.put("timestamp", "");
+            statuses.add(entry);
+        }
+        return ResponseEntity.ok().header("Content-Type", "application/json")
+                .body(new ObjectMapper().writeValueAsString(statuses));
+    }
+
+    // --- helpers ---
+
+    private String getRoleId(ApiClient client, String documentId, String roleName) throws SignNowApiException {
+        DocumentGetRequest req = new DocumentGetRequest();
+        req.withDocumentId(documentId);
+        DocumentGetResponse resp = (DocumentGetResponse) client.send(req).getResponse();
+        return resp.getRoles().stream()
+                .filter(r -> roleName.equals(r.getName()))
+                .findFirst()
+                .map(r -> r.getUniqueId())
+                .orElseThrow(() -> new IllegalArgumentException("Role '" + roleName + "' not found"));
+    }
+
+    private String getInviteLink(ApiClient client, String documentId, String inviteId, String redirectUrl)
+            throws SignNowApiException, IOException {
+        DocumentInviteLinkPostRequest linkReq = new DocumentInviteLinkPostRequest("none", 15);
+        linkReq.withFieldInviteId(inviteId);
+        linkReq.withDocumentId(documentId);
+        DocumentInviteLinkPostResponse linkResp = (DocumentInviteLinkPostResponse) client.send(linkReq).getResponse();
+        return linkResp.getData().getLink() + "&redirect_uri=" + URLEncoder.encode(redirectUrl, StandardCharsets.UTF_8);
+    }
+
+    private String getInviteIdForRoleName(ApiClient client, String documentId, String roleName)
+            throws SignNowApiException {
+        String roleId = getRoleId(client, documentId, roleName);
+        DocumentGetRequest req = new DocumentGetRequest();
+        req.withDocumentId(documentId);
+        DocumentGetResponse resp = (DocumentGetResponse) client.send(req).getResponse();
+        for (var invite : resp.getFieldInvites()) {
+            if (roleId.equals(invite.getRoleId())) {
+                return invite.getId();
+            }
+        }
+        throw new IllegalArgumentException("Invite for role '" + roleName + "' not found");
+    }
+
+    private File downloadDocument(ApiClient client, String documentId) throws SignNowApiException {
+        DocumentDownloadGetRequest req = new DocumentDownloadGetRequest();
+        req.withDocumentId(documentId).withType("collapsed");
+        DocumentDownloadGetResponse resp = (DocumentDownloadGetResponse) client.send(req).getResponse();
+        return resp.getFile();
+    }
+
+    private String makeRedirectUrl(String documentId, String nextStep) {
+        return AppConfig.sampleUrl(SAMPLE_NAME) + "?document_id=" + documentId + "&step=" + nextStep;
+    }
+
+    private static String firstName(String fullName) {
+        if (fullName == null || fullName.isBlank()) return "";
+        String[] parts = fullName.trim().split("\\s+");
+        return parts[0];
+    }
+
+    private static String lastName(String fullName) {
+        if (fullName == null || fullName.isBlank()) return "";
+        String[] parts = fullName.trim().split("\\s+");
+        return parts.length > 1 ? parts[parts.length - 1] : parts[0];
+    }
+}
diff --git a/src/main/java/com/signnow/samples/EmbeddedEditingAndSigningDG/IndexController.java b/src/main/java/com/signnow/samples/EmbeddedEditingAndSigningDG/IndexController.java
index d8f388a..e3bf8ab 100644
--- a/src/main/java/com/signnow/samples/EmbeddedEditingAndSigningDG/IndexController.java
+++ b/src/main/java/com/signnow/samples/EmbeddedEditingAndSigningDG/IndexController.java
@@ -14,6 +14,7 @@
 import com.signnow.core.ApiClient;
 import com.signnow.core.exception.SignNowApiException;
 import com.signnow.javasampleapp.ExampleInterface;
+import com.signnow.javasampleapp.config.AppConfig;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
 import com.signnow.api.document.response.DocumentDownloadGetResponse;
@@ -198,7 +199,7 @@ private void updateDocumentGroupRecipients(ApiClient client, String documentGrou
     }
 
     private String createEmbeddedEditLink(ApiClient client, String documentGroupId) throws SignNowApiException {
-        String redirectUrl = "http://localhost:8080/samples/EmbeddedEditingAndSigningDG?page=page2-embedded-sending&document_group_id=" + documentGroupId;
+        String redirectUrl = AppConfig.sampleUrl("EmbeddedEditingAndSigningDG") + "?page=page2-embedded-sending&document_group_id=" + documentGroupId;
 
         var request = new com.signnow.api.embeddededitor.request.DocumentGroupEmbeddedEditorLinkPostRequest(
                 redirectUrl, "self", 15
@@ -218,7 +219,7 @@ private String createEmbeddedInvite(ApiClient client, String documentGroupId, St
         String recipient1Email = findEmailByRoleName(recipientsResp, ROLE_RECIPIENT_1);
         String recipient2Email = findEmailByRoleName(recipientsResp, ROLE_RECIPIENT_2);
 
-        String redirectUrl = "http://localhost:8080/samples/EmbeddedEditingAndSigningDG?page=page4-status-download&document_group_id=" + documentGroupId;
+        String redirectUrl = AppConfig.sampleUrl("EmbeddedEditingAndSigningDG") + "?page=page4-status-download&document_group_id=" + documentGroupId;
 
         // -- Build invite list
         java.util.List<com.signnow.api.embeddedgroupinvite.request.data.invite.Invite> inviteSteps = new LinkedList<>();
diff --git a/src/main/java/com/signnow/samples/EmbeddedSenderWithFormAndFirstSigner/IndexController.java b/src/main/java/com/signnow/samples/EmbeddedSenderWithFormAndFirstSigner/IndexController.java
index 948fe3f..e1e5fdd 100644
--- a/src/main/java/com/signnow/samples/EmbeddedSenderWithFormAndFirstSigner/IndexController.java
+++ b/src/main/java/com/signnow/samples/EmbeddedSenderWithFormAndFirstSigner/IndexController.java
@@ -10,6 +10,7 @@
 import com.signnow.core.ApiClient;
 import com.signnow.core.exception.SignNowApiException;
 import com.signnow.javasampleapp.ExampleInterface;
+import com.signnow.javasampleapp.config.AppConfig;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
 
@@ -39,10 +40,7 @@
 @Controller
 public class IndexController implements ExampleInterface {
 
-    // Demo configuration - in production, these would come from environment/config
     private static final String DOCUMENT_GROUP_TEMPLATE_ID = "8e36720a436041ea837dc543ec00a3bc3559df45";
-    private static final String USER_EMAIL = "example@example.com"; // Demo user
-    private static final String USER_PASSWORD = "example"; // Demo password
 
     // Demo field names that might exist in templates
     private static final String CUSTOMER_NAME_FIELD = "CustomerName";
@@ -52,8 +50,6 @@ public class IndexController implements ExampleInterface {
     private static final String PREPARE_CONTRACT_ROLE = "Prepare Contract";
     private static final String CUSTOMER_SIGN_ROLE = "Customer to Sign";
 
-    // Demo URL constants
-    private static final String REDIRECT_BASE_URL = "http://localhost:8080/samples/EmbeddedSenderWithFormAndFirstSigner";
     private static final String SIGNING_URL_BASE = "https://app.signnow.com/webapp/documentgroup/signing";
 
     @Override
@@ -126,7 +122,7 @@ private ResponseEntity<?> prepareDocumentGroup(Map<String, Object> data, ApiClie
 
         // Demo: Step 3 - Add recipients to Document Group with different emails for different roles
         String customerEmail = email; // Email from form for "Customer to Sign"
-        String preparerEmail = USER_EMAIL; // Email from config for "Prepare Contract"
+        String preparerEmail = AppConfig.demoUserEmail(); // Email from config for "Prepare Contract"
         Map<String, Object> addRecipientsResponse = updateDocumentGroupRecipients(
             client, documentGroupId, customerEmail, preparerEmail
         );
@@ -339,7 +335,7 @@ private String getEmailForRole(String recipientName, String customerEmail, Strin
 
     private Map<String, Object> createEmbeddedSendingUrl(ApiClient client, String documentGroupId) throws SignNowApiException {
         // Demo: Create embedded sending URL with redirect back to demo app
-        String redirectUrl = REDIRECT_BASE_URL + "?page=signing-page&document_group_id=" + documentGroupId;
+        String redirectUrl = AppConfig.sampleUrl("EmbeddedSenderWithFormAndFirstSigner") + "?page=signing-page&document_group_id=" + documentGroupId;
 
         var embeddedSendingRequest = new com.signnow.api.embeddedsending.request.DocumentGroupEmbeddedSendingLinkPostRequest(
             redirectUrl,  // Demo: Redirect back to our demo app
@@ -372,7 +368,7 @@ private Map<String, Object> createSigningLink(ApiClient client, String documentG
         String accessToken = (String) limitedTokenResponse.get("access_token");
 
         // Demo: Build signing URL with parameters - redirect to status page after signing
-        String redirectUrl = REDIRECT_BASE_URL + "?page=status-page&document_group_id=" + documentGroupId;
+        String redirectUrl = AppConfig.sampleUrl("EmbeddedSenderWithFormAndFirstSigner") + "?page=status-page&document_group_id=" + documentGroupId;
 
         String signingUrl = SIGNING_URL_BASE + "?" +
             "document_group_id=" + documentGroupId +
@@ -390,8 +386,8 @@ private Map<String, Object> createSigningLink(ApiClient client, String documentG
     private Map<String, Object> generateLimitedToken(ApiClient client, String documentGroupId) throws SignNowApiException {
         // Demo: Create token request with limited scope for document group
         var tokenRequest = new com.signnow.api.auth.request.TokenPostRequest(
-            USER_EMAIL,
-            USER_PASSWORD,
+            AppConfig.demoUserEmail(),
+            AppConfig.demoUserPassword(),
             "limited_signer_scope_token_for_document_group_invite/" + documentGroupId,
             "password",
             ""
diff --git a/src/main/java/com/signnow/samples/EmbeddedSenderWithFormCreditLoanAgreement/IndexController.java b/src/main/java/com/signnow/samples/EmbeddedSenderWithFormCreditLoanAgreement/IndexController.java
index 9f64ebb..dc2bf45 100644
--- a/src/main/java/com/signnow/samples/EmbeddedSenderWithFormCreditLoanAgreement/IndexController.java
+++ b/src/main/java/com/signnow/samples/EmbeddedSenderWithFormCreditLoanAgreement/IndexController.java
@@ -14,6 +14,7 @@
 import com.signnow.core.ApiClient;
 import com.signnow.core.exception.SignNowApiException;
 import com.signnow.javasampleapp.ExampleInterface;
+import com.signnow.javasampleapp.config.AppConfig;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
 import com.signnow.api.document.response.DocumentDownloadGetResponse;
@@ -98,7 +99,7 @@ private void prefillFields(ApiClient client, String documentId, String fullName)
     }
 
     private String getEmbeddedSendingLink(ApiClient client, String documentId) throws SignNowApiException {
-        String redirectUrl = "http://localhost:8080/samples/EmbeddedSenderWithFormCreditLoanAgreement?page=download-with-status&document_id=" + documentId;
+        String redirectUrl = AppConfig.sampleUrl("EmbeddedSenderWithFormCreditLoanAgreement") + "?page=download-with-status&document_id=" + documentId;
 
         DocumentEmbeddedSendingLinkPostRequest request = new DocumentEmbeddedSendingLinkPostRequest("invite", redirectUrl, 16, "self");
         request.withDocumentId(documentId);
diff --git a/src/main/java/com/signnow/samples/EmbeddedSenderWithFormDG/IndexController.java b/src/main/java/com/signnow/samples/EmbeddedSenderWithFormDG/IndexController.java
index d3fab8b..50f014e 100644
--- a/src/main/java/com/signnow/samples/EmbeddedSenderWithFormDG/IndexController.java
+++ b/src/main/java/com/signnow/samples/EmbeddedSenderWithFormDG/IndexController.java
@@ -10,6 +10,7 @@
 import com.signnow.core.ApiClient;
 import com.signnow.core.exception.SignNowApiException;
 import com.signnow.javasampleapp.ExampleInterface;
+import com.signnow.javasampleapp.config.AppConfig;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
 
@@ -39,19 +40,12 @@
 @Controller
 public class IndexController implements ExampleInterface {
 
-    // Demo configuration - in production, these would come from environment/config
     private static final String DOCUMENT_GROUP_TEMPLATE_ID = "c8040bbc40804b89b63a0fa8c79b42a7ae4818c1";
-    private static final String USER_EMAIL = "example@example.com"; // Demo user
-
-    // Demo field names that might exist in templates
 
     // Demo recipient roles
     private static final String PREPARE_CONTRACT_ROLE = "Prepare Contract";
     private static final String CUSTOMER_SIGN_ROLE = "Customer to Sign";
 
-    // Demo URL constants
-    private static final String REDIRECT_BASE_URL = "http://localhost:8080/samples/EmbeddedSenderWithFormDG";
-
     @Override
     public ResponseEntity<String> handleGet(Map<String, String> queryParams) throws IOException {
         // Demo: Simple HTML page serving - use classpath resource
@@ -121,7 +115,7 @@ private ResponseEntity<?> prepareDocumentGroup(Map<String, Object> data, ApiClie
 
         // Demo: Step 3 - Add recipients to Document Group with different emails for different roles
         String customerEmail = email; // Email from form for "Customer to Sign"
-        String preparerEmail = USER_EMAIL; // Email from config for "Prepare Contract"
+        String preparerEmail = AppConfig.demoUserEmail(); // Email from config for "Prepare Contract"
         Map<String, Object> addRecipientsResponse = updateDocumentGroupRecipients(
             client, documentGroupId, customerEmail, preparerEmail
         );
@@ -324,7 +318,7 @@ private Map<String, Object> updateDocumentGroupRecipients(
 
     private Map<String, Object> createEmbeddedSendingUrl(ApiClient client, String documentGroupId) throws SignNowApiException {
         // Demo: Create embedded sending URL with redirect back to status page
-        String redirectUrl = REDIRECT_BASE_URL + "?" +
+        String redirectUrl = AppConfig.sampleUrl("EmbeddedSenderWithFormDG") + "?" +
             "page=status-page&document_group_id=" + documentGroupId;
 
         var embeddedSendingRequest = new com.signnow.api.embeddedsending.request.DocumentGroupEmbeddedSendingLinkPostRequest(
diff --git a/src/main/java/com/signnow/samples/EmbeddedSenderWithFormDGAdjunct/IndexController.java b/src/main/java/com/signnow/samples/EmbeddedSenderWithFormDGAdjunct/IndexController.java
index 7424ad6..108f171 100644
--- a/src/main/java/com/signnow/samples/EmbeddedSenderWithFormDGAdjunct/IndexController.java
+++ b/src/main/java/com/signnow/samples/EmbeddedSenderWithFormDGAdjunct/IndexController.java
@@ -10,6 +10,7 @@
 import com.signnow.core.ApiClient;
 import com.signnow.core.exception.SignNowApiException;
 import com.signnow.javasampleapp.ExampleInterface;
+import com.signnow.javasampleapp.config.AppConfig;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
 
@@ -40,19 +41,12 @@
 @Controller
 public class IndexController implements ExampleInterface {
 
-    // Demo configuration - in production, these would come from environment/config
     private static final String DOCUMENT_GROUP_TEMPLATE_ID = "e486ebf3fb814d55888bcbf75ceaf62b6db0de5a";
-    private static final String USER_EMAIL = "example@example.com"; // Demo user
-
-    // Demo field names that might exist in templates
 
     // Demo recipient roles
     private static final String PREPARE_CONTRACT_ROLE = "Prepare Contract";
     private static final String CUSTOMER_SIGN_ROLE = "Customer to Sign";
 
-    // Demo URL constants
-    private static final String REDIRECT_BASE_URL = "http://localhost:8080/samples/EmbeddedSenderWithFormDGAdjunct";
-
     @Override
         public ResponseEntity<String> handleGet(Map<String, String> queryParams) throws IOException {
         // Demo: Simple HTML page serving
@@ -122,7 +116,7 @@ private ResponseEntity<?> prepareDocumentGroup(Map<String, Object> data, ApiClie
 
         // Demo: Step 3 - Add recipients to Document Group with different emails for different roles
         String customerEmail = email; // Email from form for "Customer to Sign"
-        String preparerEmail = USER_EMAIL; // Email from config for "Prepare Contract"
+        String preparerEmail = AppConfig.demoUserEmail(); // Email from config for "Prepare Contract"
         Map<String, Object> addRecipientsResponse = updateDocumentGroupRecipients(
             client, documentGroupId, customerEmail, preparerEmail
         );
@@ -325,7 +319,7 @@ private Map<String, Object> updateDocumentGroupRecipients(
 
     private Map<String, Object> createEmbeddedSendingUrl(ApiClient client, String documentGroupId) throws SignNowApiException {
         // Demo: Create embedded sending URL with redirect back to status page
-        String redirectUrl = REDIRECT_BASE_URL + "?" +
+        String redirectUrl = AppConfig.sampleUrl("EmbeddedSenderWithFormDGAdjunct") + "?" +
             "page=status-page&document_group_id=" + documentGroupId;
 
         var embeddedSendingRequest = new com.signnow.api.embeddedsending.request.DocumentGroupEmbeddedSendingLinkPostRequest(
diff --git a/src/main/java/com/signnow/samples/EmbeddedSenderWithFormDGConstr/IndexController.java b/src/main/java/com/signnow/samples/EmbeddedSenderWithFormDGConstr/IndexController.java
index 8b5a413..2fd2202 100644
--- a/src/main/java/com/signnow/samples/EmbeddedSenderWithFormDGConstr/IndexController.java
+++ b/src/main/java/com/signnow/samples/EmbeddedSenderWithFormDGConstr/IndexController.java
@@ -10,6 +10,7 @@
 import com.signnow.core.ApiClient;
 import com.signnow.core.exception.SignNowApiException;
 import com.signnow.javasampleapp.ExampleInterface;
+import com.signnow.javasampleapp.config.AppConfig;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
 
@@ -40,19 +41,12 @@
 @Controller
 public class IndexController implements ExampleInterface {
 
-    // Demo configuration - in production, these would come from environment/config
     private static final String DOCUMENT_GROUP_TEMPLATE_ID = "625ae557229d48d78728c281f46d3d8494f235a4";
-    private static final String USER_EMAIL = "example@example.com"; // Demo user
-
-    // Demo field names that might exist in templates
 
     // Demo recipient roles
     private static final String PREPARE_CONTRACT_ROLE = "Prepare Contract";
     private static final String CUSTOMER_SIGN_ROLE = "Customer to Sign";
 
-    // Demo URL constants
-    private static final String REDIRECT_BASE_URL = "http://localhost:8080/samples/EmbeddedSenderWithFormDGConstr";
-
     @Override
         public ResponseEntity<String> handleGet(Map<String, String> queryParams) throws IOException {
         // Demo: Simple HTML page serving
@@ -122,7 +116,7 @@ private ResponseEntity<?> prepareDocumentGroup(Map<String, Object> data, ApiClie
 
         // Demo: Step 3 - Add recipients to Document Group with different emails for different roles
         String customerEmail = email; // Email from form for "Customer to Sign"
-        String preparerEmail = USER_EMAIL; // Email from config for "Prepare Contract"
+        String preparerEmail = AppConfig.demoUserEmail(); // Email from config for "Prepare Contract"
         Map<String, Object> addRecipientsResponse = updateDocumentGroupRecipients(
             client, documentGroupId, customerEmail, preparerEmail
         );
@@ -325,7 +319,7 @@ private Map<String, Object> updateDocumentGroupRecipients(
 
     private Map<String, Object> createEmbeddedSendingUrl(ApiClient client, String documentGroupId) throws SignNowApiException {
         // Demo: Create embedded sending URL with redirect back to status page
-        String redirectUrl = REDIRECT_BASE_URL + "?" +
+        String redirectUrl = AppConfig.sampleUrl("EmbeddedSenderWithFormDGConstr") + "?" +
             "page=status-page&document_group_id=" + documentGroupId;
 
         var embeddedSendingRequest = new com.signnow.api.embeddedsending.request.DocumentGroupEmbeddedSendingLinkPostRequest(
diff --git a/src/main/java/com/signnow/samples/EmbeddedSenderWithoutFormFile/IndexController.java b/src/main/java/com/signnow/samples/EmbeddedSenderWithoutFormFile/IndexController.java
index 7de60e3..5f2293b 100644
--- a/src/main/java/com/signnow/samples/EmbeddedSenderWithoutFormFile/IndexController.java
+++ b/src/main/java/com/signnow/samples/EmbeddedSenderWithoutFormFile/IndexController.java
@@ -11,6 +11,7 @@
 import com.signnow.core.ApiClient;
 import com.signnow.core.exception.SignNowApiException;
 import com.signnow.javasampleapp.ExampleInterface;
+import com.signnow.javasampleapp.config.AppConfig;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
 import com.signnow.api.document.response.DocumentDownloadGetResponse;
@@ -76,7 +77,7 @@ private String getEmbeddedSendingLink(ApiClient client) throws SignNowApiExcepti
         CloneTemplatePostResponse cloneResponse = createDocumentFromTemplate(client);
         String documentId = cloneResponse.getId();
 
-        String redirectUrl = "http://localhost:8080/samples/EmbeddedSenderWithoutFormFile?page=download-with-status&document_id=" + documentId;
+        String redirectUrl = AppConfig.sampleUrl("EmbeddedSenderWithoutFormFile") + "?page=download-with-status&document_id=" + documentId;
         DocumentEmbeddedSendingLinkPostRequest request = new DocumentEmbeddedSendingLinkPostRequest("document", redirectUrl, 16, "self");
         request.withDocumentId(documentId);
 
diff --git a/src/main/java/com/signnow/samples/EmbeddedSignerConsentForm/IndexController.java b/src/main/java/com/signnow/samples/EmbeddedSignerConsentForm/IndexController.java
index 8119e9f..1d66276 100644
--- a/src/main/java/com/signnow/samples/EmbeddedSignerConsentForm/IndexController.java
+++ b/src/main/java/com/signnow/samples/EmbeddedSignerConsentForm/IndexController.java
@@ -17,6 +17,7 @@
 import com.signnow.core.ApiClient;
 import com.signnow.core.exception.SignNowApiException;
 import com.signnow.javasampleapp.ExampleInterface;
+import com.signnow.javasampleapp.config.AppConfig;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
 
@@ -87,7 +88,7 @@ private String getEmbeddedInviteLink(ApiClient client, String documentId, String
 
         DocumentInviteLinkPostResponse embeddedInviteResponse = (DocumentInviteLinkPostResponse) client.send(embeddedInvite).getResponse();
 
-        String redirectUrl = "http://localhost:8080/samples/EmbeddedSignerConsentForm?page=download-container&document_id=" + documentId;
+        String redirectUrl = AppConfig.sampleUrl("EmbeddedSignerConsentForm") + "?page=download-container&document_id=" + documentId;
         return embeddedInviteResponse.getData().getLink() + "&redirect_uri=" + java.net.URLEncoder.encode(redirectUrl, "UTF-8");
     }
 
diff --git a/src/main/java/com/signnow/samples/EmbeddedSignerConsumerServices/IndexController.java b/src/main/java/com/signnow/samples/EmbeddedSignerConsumerServices/IndexController.java
index bd9a9d0..a5ad43c 100644
--- a/src/main/java/com/signnow/samples/EmbeddedSignerConsumerServices/IndexController.java
+++ b/src/main/java/com/signnow/samples/EmbeddedSignerConsumerServices/IndexController.java
@@ -19,6 +19,7 @@
 import com.signnow.core.ApiClient;
 import com.signnow.core.exception.SignNowApiException;
 import com.signnow.javasampleapp.ExampleInterface;
+import com.signnow.javasampleapp.config.AppConfig;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
 
@@ -154,7 +155,7 @@ private String getEmbeddedInviteLink(ApiClient client, String documentId, String
 
         DocumentInviteLinkPostResponse embeddedInviteResponse = (DocumentInviteLinkPostResponse) client.send(embeddedInvite).getResponse();
 
-        String redirectUrl = "http://localhost:8080/samples/EmbeddedSignerConsumerServices?page=finish&document_id=" + documentId;
+        String redirectUrl = AppConfig.sampleUrl("EmbeddedSignerConsumerServices") + "?page=finish&document_id=" + documentId;
 
         return embeddedInviteResponse.getData().getLink() + "&redirect_uri=" + java.net.URLEncoder.encode(redirectUrl, "UTF-8");
     }
diff --git a/src/main/java/com/signnow/samples/EmbeddedSignerPatientIntakeForm/IndexController.java b/src/main/java/com/signnow/samples/EmbeddedSignerPatientIntakeForm/IndexController.java
index 7dea0b9..f84c31f 100644
--- a/src/main/java/com/signnow/samples/EmbeddedSignerPatientIntakeForm/IndexController.java
+++ b/src/main/java/com/signnow/samples/EmbeddedSignerPatientIntakeForm/IndexController.java
@@ -19,6 +19,7 @@
 import com.signnow.core.ApiClient;
 import com.signnow.core.exception.SignNowApiException;
 import com.signnow.javasampleapp.ExampleInterface;
+import com.signnow.javasampleapp.config.AppConfig;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
 
@@ -160,7 +161,7 @@ private String getEmbeddedInviteLink(ApiClient client, String documentId, String
 
         DocumentInviteLinkPostResponse embeddedInviteResponse = (DocumentInviteLinkPostResponse) client.send(embeddedInvite).getResponse();
 
-        String redirectUrl = "http://localhost:8080/samples/EmbeddedSignerPatientIntakeForm?page=download-container&document_id=" + documentId;
+        String redirectUrl = AppConfig.sampleUrl("EmbeddedSignerPatientIntakeForm") + "?page=download-container&document_id=" + documentId;
 
         return embeddedInviteResponse.getData().getLink() + "&redirect_uri=" + java.net.URLEncoder.encode(redirectUrl, "UTF-8");
     }
diff --git a/src/main/java/com/signnow/samples/EmbeddedSignerWithFormInsurance/IndexController.java b/src/main/java/com/signnow/samples/EmbeddedSignerWithFormInsurance/IndexController.java
index d2c8753..ee3df4c 100644
--- a/src/main/java/com/signnow/samples/EmbeddedSignerWithFormInsurance/IndexController.java
+++ b/src/main/java/com/signnow/samples/EmbeddedSignerWithFormInsurance/IndexController.java
@@ -18,6 +18,7 @@
 import com.signnow.core.ApiClient;
 import com.signnow.core.exception.SignNowApiException;
 import com.signnow.javasampleapp.ExampleInterface;
+import com.signnow.javasampleapp.config.AppConfig;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
 import com.signnow.api.document.response.DocumentDownloadGetResponse;
@@ -108,7 +109,7 @@ private String getEmbeddedInviteLink(ApiClient client, String documentId, String
 
         DocumentInviteLinkPostResponse embeddedInviteResponse = (DocumentInviteLinkPostResponse) client.send(embeddedInvite).getResponse();
 
-        String redirectUrl = "http://localhost:8080/samples/EmbeddedSignerWithFormInsurance?page=download-container&document_id=" + documentId;
+        String redirectUrl = AppConfig.sampleUrl("EmbeddedSignerWithFormInsurance") + "?page=download-container&document_id=" + documentId;
 
         return embeddedInviteResponse.getData().getLink() + "&redirect_uri=" + java.net.URLEncoder.encode(redirectUrl, "UTF-8");
     }
diff --git a/src/main/java/com/signnow/samples/HROnboardingSystem/IndexController.java b/src/main/java/com/signnow/samples/HROnboardingSystem/IndexController.java
index 9c7da8a..f0505b0 100644
--- a/src/main/java/com/signnow/samples/HROnboardingSystem/IndexController.java
+++ b/src/main/java/com/signnow/samples/HROnboardingSystem/IndexController.java
@@ -29,6 +29,7 @@
 import com.signnow.core.ApiClient;
 import com.signnow.core.exception.SignNowApiException;
 import com.signnow.javasampleapp.ExampleInterface;
+import com.signnow.javasampleapp.config.AppConfig;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
 
@@ -57,10 +58,6 @@
 @Controller
 public class IndexController implements ExampleInterface {
 
-    // Demo configuration - in production, these would come from environment/config
-    private static final String USER_EMAIL = "example@example.com"; // Demo user
-    private static final String USER_PASSWORD = "example"; // Demo password
-
     // Template IDs for HR onboarding documents
     private static final String I9_FORM_TEMPLATE_ID = "940989288b8b4c62a950b908333b5b21efd6a174";
     private static final String NDA_TEMPLATE_ID = "a4f523d0cb234ffc99b0badc9e6f59111f76abc2";
@@ -72,9 +69,6 @@ public class IndexController implements ExampleInterface {
     private static final String TEXT_FIELD_156 = "Text Field 156";
     private static final String EMAIL_FIELD = "Email";
 
-    // Demo URL constants
-    private static final String REDIRECT_BASE_URL = "http://localhost:8080/samples/HROnboardingSystem";
-
     @Override
     public ResponseEntity<String> handleGet(Map<String, String> queryParams) throws IOException {
         // Demo: Simple HTML page serving - use classpath resource
@@ -279,7 +273,7 @@ private Map<String, Object> sendInvite(ApiClient client, String documentGroupId,
                         null,
                         null,
                         null,
-                        REDIRECT_BASE_URL + "?page=status-page&document_group_id=" + documentGroupId,
+                        AppConfig.sampleUrl("HROnboardingSystem") + "?page=status-page&document_group_id=" + documentGroupId,
                         null,
                         "self",
                         null
diff --git a/src/main/java/com/signnow/samples/ISVWithFormAndOneClickSendBasicPrefill/IndexController.java b/src/main/java/com/signnow/samples/ISVWithFormAndOneClickSendBasicPrefill/IndexController.java
index 69d9623..d5ab9aa 100644
--- a/src/main/java/com/signnow/samples/ISVWithFormAndOneClickSendBasicPrefill/IndexController.java
+++ b/src/main/java/com/signnow/samples/ISVWithFormAndOneClickSendBasicPrefill/IndexController.java
@@ -10,6 +10,7 @@
 import com.signnow.core.ApiClient;
 import com.signnow.core.exception.SignNowApiException;
 import com.signnow.javasampleapp.ExampleInterface;
+import com.signnow.javasampleapp.config.AppConfig;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
 
@@ -38,18 +39,12 @@
 @Controller
 public class IndexController implements ExampleInterface {
 
-    // Demo configuration - in production, these would come from environment/config
     private static final String DOCUMENT_GROUP_TEMPLATE_ID = "6e79b9e6f9624984a7f054a7171d1644d0fb9934";
-    private static final String USER_EMAIL = "example@example.com"; // Demo user
-    private static final String USER_PASSWORD = "example"; // Demo password
 
     // Demo field names that might exist in templates
     private static final String NAME_FIELD = "Name";
     private static final String EMAIL_FIELD = "Email";
 
-    // Demo URL constants
-    private static final String REDIRECT_BASE_URL = "http://localhost:8080/samples/ISVWithFormAndOneClickSendBasicPrefill";
-
     @Override
         public ResponseEntity<String> handleGet(Map<String, String> queryParams) throws IOException {
         // Demo: Simple HTML page serving
@@ -267,7 +262,7 @@ private Map<String, Object> sendInvite(ApiClient client, String documentGroupId,
                 null,
                 null,
                 null,
-                REDIRECT_BASE_URL + "?page=status-page&document_group_id=" + documentGroupId, // redirectUri
+                AppConfig.sampleUrl("ISVWithFormAndOneClickSendBasicPrefill") + "?page=status-page&document_group_id=" + documentGroupId, // redirectUri
                 null,
                 "self", // redirectTarget
                 null
diff --git a/src/main/java/com/signnow/samples/ISVWithFormAndOneClickSendMergeFields/IndexController.java b/src/main/java/com/signnow/samples/ISVWithFormAndOneClickSendMergeFields/IndexController.java
index d6c06bc..e541ab7 100644
--- a/src/main/java/com/signnow/samples/ISVWithFormAndOneClickSendMergeFields/IndexController.java
+++ b/src/main/java/com/signnow/samples/ISVWithFormAndOneClickSendMergeFields/IndexController.java
@@ -12,6 +12,7 @@
 import com.signnow.core.ApiClient;
 import com.signnow.core.exception.SignNowApiException;
 import com.signnow.javasampleapp.ExampleInterface;
+import com.signnow.javasampleapp.config.AppConfig;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
 
@@ -41,10 +42,7 @@
 @Controller
 public class IndexController implements ExampleInterface {
 
-    // Demo configuration - in production, these would come from environment/config
     private static final String DOCUMENT_GROUP_TEMPLATE_ID = "8e36720a436041ea837dc543ec00a3bc3559df45";
-    private static final String USER_EMAIL = "example@example.com"; // Demo user
-    private static final String USER_PASSWORD = "example"; // Demo password
 
     // Demo field names that might exist in templates
     private static final String CUSTOMER_NAME_FIELD = "CustomerName";
@@ -54,9 +52,6 @@ public class IndexController implements ExampleInterface {
     private static final String PREPARE_CONTRACT_ROLE = "Prepare Contract";
     private static final String CUSTOMER_SIGN_ROLE = "Customer to Sign";
 
-    // Demo URL constants
-    private static final String REDIRECT_BASE_URL = "http://localhost:8080/samples/ISVWithFormAndOneClickSendMergeFields";
-
     @Override
     public ResponseEntity<String> handleGet(Map<String, String> queryParams) throws IOException {
         // Demo: Simple HTML page serving - use classpath resource
@@ -354,17 +349,6 @@ private Map<String, Object> sendInvite(ApiClient client, String documentGroupId,
 
         // Get recipients to use their roles
         var recipientsResponse = getDocumentGroupRecipients(client, documentGroupId);
-        
-        // Debug: Print recipients response as JSON
-        try {
-            ObjectMapper mapper = new ObjectMapper();
-            String jsonResponse = mapper.writeValueAsString(recipientsResponse);
-            System.out.println("DEBUG: DocumentGroupRecipientsGetResponse JSON:");
-            System.out.println(jsonResponse);
-        } catch (Exception e) {
-            System.out.println("DEBUG: Error serializing DocumentGroupRecipientsGetResponse: " + e.getMessage());
-        }
-        
         var recipients = recipientsResponse.getData().getRecipients();
 
         // Check if we have recipients
@@ -386,7 +370,7 @@ private Map<String, Object> sendInvite(ApiClient client, String documentGroupId,
                 emailToUse = email; // Use form email for "Prepare Contract"
             } else if (CUSTOMER_SIGN_ROLE.equals(recipient.getName())) {
                 // Use config email for "Customer to Sign"
-                emailToUse = USER_EMAIL;
+                emailToUse = AppConfig.demoUserEmail();
             }
 
             // Create invite email for this recipient
@@ -411,7 +395,7 @@ private Map<String, Object> sendInvite(ApiClient client, String documentGroupId,
                     null,
                     null,
                     null,
-                    REDIRECT_BASE_URL + "?page=status-page&document_group_id=" + documentGroupId, // redirectUri
+                    AppConfig.sampleUrl("ISVWithFormAndOneClickSendMergeFields") + "?page=status-page&document_group_id=" + documentGroupId, // redirectUri
                     null,
                     "self", // redirectTarget
                     null
diff --git a/src/main/java/com/signnow/samples/MedicalInsuranceClaimForm/IndexController.java b/src/main/java/com/signnow/samples/MedicalInsuranceClaimForm/IndexController.java
index 3331810..87e8afa 100644
--- a/src/main/java/com/signnow/samples/MedicalInsuranceClaimForm/IndexController.java
+++ b/src/main/java/com/signnow/samples/MedicalInsuranceClaimForm/IndexController.java
@@ -21,6 +21,7 @@
 import com.signnow.core.ApiClient;
 import com.signnow.core.exception.SignNowApiException;
 import com.signnow.javasampleapp.ExampleInterface;
+import com.signnow.javasampleapp.config.AppConfig;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
 
@@ -170,7 +171,7 @@ private String getEmbeddedInviteLink(ApiClient client, String documentId, String
 
         DocumentInviteLinkPostResponse embeddedInviteResponse = (DocumentInviteLinkPostResponse) client.send(embeddedInvite).getResponse();
 
-        String redirectUrl = "http://localhost:8080/samples/MedicalInsuranceClaimForm?page=download-container&document_id=" + documentId;
+        String redirectUrl = AppConfig.sampleUrl("MedicalInsuranceClaimForm") + "?page=download-container&document_id=" + documentId;
 
         return embeddedInviteResponse.getData().getLink() + "&redirect_uri=" + java.net.URLEncoder.encode(redirectUrl, "UTF-8");
     }
diff --git a/src/main/java/com/signnow/samples/PrefillAndEmbeddedSendingAgreement/IndexController.java b/src/main/java/com/signnow/samples/PrefillAndEmbeddedSendingAgreement/IndexController.java
index 5f72e3b..fed4802 100644
--- a/src/main/java/com/signnow/samples/PrefillAndEmbeddedSendingAgreement/IndexController.java
+++ b/src/main/java/com/signnow/samples/PrefillAndEmbeddedSendingAgreement/IndexController.java
@@ -14,6 +14,7 @@
 import com.signnow.core.ApiClient;
 import com.signnow.core.exception.SignNowApiException;
 import com.signnow.javasampleapp.ExampleInterface;
+import com.signnow.javasampleapp.config.AppConfig;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
 import com.signnow.api.document.response.DocumentDownloadGetResponse;
@@ -97,7 +98,7 @@ private void prefillFields(ApiClient client, String documentId, String name) thr
     }
 
     private String getEmbeddedSendingLink(ApiClient client, String documentId) throws SignNowApiException {
-        String redirectUrl = "http://localhost:8080/samples/PrefillAndEmbeddedSendingAgreement?page=download-with-status&document_id=" + documentId;
+        String redirectUrl = AppConfig.sampleUrl("PrefillAndEmbeddedSendingAgreement") + "?page=download-with-status&document_id=" + documentId;
 
         DocumentEmbeddedSendingLinkPostRequest request = new DocumentEmbeddedSendingLinkPostRequest("document", redirectUrl, 16, "self");
         request.withDocumentId(documentId);
diff --git a/src/main/java/com/signnow/samples/UploadEmbeddedEditingAndInvite/IndexController.java b/src/main/java/com/signnow/samples/UploadEmbeddedEditingAndInvite/IndexController.java
new file mode 100644
index 0000000..7e1d742
--- /dev/null
+++ b/src/main/java/com/signnow/samples/UploadEmbeddedEditingAndInvite/IndexController.java
@@ -0,0 +1,203 @@
+package com.signnow.samples.UploadEmbeddedEditingAndInvite;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.signnow.Sdk;
+import com.signnow.api.document.request.DocumentDownloadGetRequest;
+import com.signnow.api.document.response.DocumentDownloadGetResponse;
+import com.signnow.api.document.request.DocumentGetRequest;
+import com.signnow.api.document.response.DocumentGetResponse;
+import com.signnow.api.document.request.DocumentPostRequest;
+import com.signnow.api.document.response.DocumentPostResponse;
+import com.signnow.api.documentinvite.request.SendInvitePostRequest;
+import com.signnow.api.documentinvite.request.data.To;
+import com.signnow.api.documentinvite.request.data.ToCollection;
+import com.signnow.api.embeddededitor.request.DocumentEmbeddedEditorLinkPostRequest;
+import com.signnow.api.embeddededitor.response.DocumentEmbeddedEditorLinkPostResponse;
+import com.signnow.core.ApiClient;
+import com.signnow.core.exception.SignNowApiException;
+import com.signnow.javasampleapp.ExampleInterface;
+import com.signnow.javasampleapp.config.AppConfig;
+import org.springframework.http.ResponseEntity;
+import org.springframework.stereotype.Controller;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.HashMap;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+
+@Controller
+public class IndexController implements ExampleInterface {
+
+    private static final String SAMPLE_NAME = "UploadEmbeddedEditingAndInvite";
+    private static final String SENDER_EMAIL = "sender@signnow.com";
+    private static final String PDF_PATH =
+            "src/main/resources/static/samples/UploadEmbeddedSender/Sales Proposal.pdf";
+
+    @Override
+    public ResponseEntity<String> handleGet(Map<String, String> queryParams) throws IOException {
+        try (var inputStream = getClass().getResourceAsStream("/static/samples/" + SAMPLE_NAME + "/index.html")) {
+            if (inputStream == null) {
+                throw new IOException("HTML file not found in classpath");
+            }
+            String html = new String(inputStream.readAllBytes());
+            return ResponseEntity.ok().header("Content-Type", "text/html").body(html);
+        }
+    }
+
+    @Override
+    public ResponseEntity<?> handlePost(String formData) throws IOException, SignNowApiException {
+        Map<String, Object> data = new ObjectMapper().readValue(formData, Map.class);
+        String action = (String) data.getOrDefault("action", "");
+
+        ApiClient client = new Sdk().build().authenticate().getApiClient();
+
+        switch (action) {
+            case "upload_and_create_dg":
+                return uploadDocument(client);
+            case "create_embedded_edit":
+                return createEmbeddedEdit(client, data);
+            case "create_invite":
+                return createInvite(client, data);
+            case "invite-status":
+                return inviteStatus(client, data);
+            case "download-document":
+                return downloadDocument(client, data);
+            default:
+                Map<String, Object> error = new HashMap<>();
+                error.put("success", false);
+                error.put("message", "Invalid action");
+                return ResponseEntity.badRequest().body(new ObjectMapper().writeValueAsString(error));
+        }
+    }
+
+    private ResponseEntity<?> uploadDocument(ApiClient client) throws SignNowApiException, IOException {
+        if (!Files.exists(Paths.get(PDF_PATH))) {
+            Map<String, Object> error = new HashMap<>();
+            error.put("success", false);
+            error.put("message", "PDF file not found: " + PDF_PATH);
+            return ResponseEntity.status(500).body(new ObjectMapper().writeValueAsString(error));
+        }
+
+        DocumentPostRequest req = new DocumentPostRequest(new File(PDF_PATH), "Sales Proposal");
+        DocumentPostResponse resp = (DocumentPostResponse) client.send(req).getResponse();
+
+        Map<String, Object> result = new HashMap<>();
+        result.put("success", true);
+        result.put("message", "Document uploaded successfully");
+        result.put("document_id", resp.getId());
+        return ResponseEntity.ok().header("Content-Type", "application/json")
+                .body(new ObjectMapper().writeValueAsString(result));
+    }
+
+    private ResponseEntity<?> createEmbeddedEdit(ApiClient client, Map<String, Object> data)
+            throws SignNowApiException, IOException {
+        String documentId = (String) data.get("document_id");
+        if (documentId == null || documentId.isBlank()) {
+            Map<String, Object> error = new HashMap<>();
+            error.put("success", false);
+            error.put("message", "Document ID is required");
+            return ResponseEntity.badRequest().body(new ObjectMapper().writeValueAsString(error));
+        }
+
+        String redirectUrl = AppConfig.sampleUrl(SAMPLE_NAME) + "?page=invite-page&document_id=" + documentId;
+
+        DocumentEmbeddedEditorLinkPostRequest req =
+                new DocumentEmbeddedEditorLinkPostRequest(redirectUrl, "self", 15);
+        req.withDocumentId(documentId);
+        DocumentEmbeddedEditorLinkPostResponse resp =
+                (DocumentEmbeddedEditorLinkPostResponse) client.send(req).getResponse();
+
+        Map<String, Object> result = new HashMap<>();
+        result.put("success", true);
+        result.put("edit_link", resp.getData().getUrl());
+        return ResponseEntity.ok().header("Content-Type", "application/json")
+                .body(new ObjectMapper().writeValueAsString(result));
+    }
+
+    private ResponseEntity<?> createInvite(ApiClient client, Map<String, Object> data)
+            throws SignNowApiException, IOException {
+        String documentId  = (String) data.get("document_id");
+        String signerEmail = (String) data.getOrDefault("signer_email", "");
+        String signerName  = (String) data.getOrDefault("signer_name", "");
+
+        if (documentId == null || signerEmail.isBlank() || signerName.isBlank()) {
+            Map<String, Object> error = new HashMap<>();
+            error.put("success", false);
+            error.put("message", "Document ID, signer email and name are required");
+            return ResponseEntity.badRequest().body(new ObjectMapper().writeValueAsString(error));
+        }
+
+        DocumentGetRequest docReq = new DocumentGetRequest();
+        docReq.withDocumentId(documentId);
+        DocumentGetResponse docResp = (DocumentGetResponse) client.send(docReq).getResponse();
+
+        String redirectUri = AppConfig.sampleUrl(SAMPLE_NAME) + "?page=status-page&document_id=" + documentId;
+
+        ToCollection toCollection = new ToCollection();
+        for (var role : docResp.getRoles()) {
+            toCollection.add(new To(
+                    signerEmail,
+                    role.getUniqueId(),
+                    role.getName(),
+                    1,
+                    "Document Signing Request - Action Required",
+                    "Dear " + signerName + ", please review and sign the uploaded document."
+            ));
+        }
+
+        SendInvitePostRequest inviteReq = new SendInvitePostRequest(
+                documentId, toCollection, SENDER_EMAIL,
+                "Document Signing Request - Action Required",
+                "Dear " + signerName + ", please review and sign the uploaded document."
+        );
+        client.send(inviteReq);
+
+        Map<String, Object> result = new HashMap<>();
+        result.put("success", true);
+        result.put("message", "Invite sent successfully");
+        return ResponseEntity.ok().header("Content-Type", "application/json")
+                .body(new ObjectMapper().writeValueAsString(result));
+    }
+
+    private ResponseEntity<?> inviteStatus(ApiClient client, Map<String, Object> data)
+            throws SignNowApiException, IOException {
+        String documentId = (String) data.get("document_id");
+
+        DocumentGetRequest req = new DocumentGetRequest();
+        req.withDocumentId(documentId);
+        DocumentGetResponse resp = (DocumentGetResponse) client.send(req).getResponse();
+
+        List<Map<String, Object>> statuses = new LinkedList<>();
+        for (var invite : resp.getFieldInvites()) {
+            Map<String, Object> entry = new HashMap<>();
+            entry.put("name", invite.getEmail());
+            entry.put("status", invite.getStatus());
+            entry.put("timestamp", "");
+            statuses.add(entry);
+        }
+        return ResponseEntity.ok().header("Content-Type", "application/json")
+                .body(new ObjectMapper().writeValueAsString(statuses));
+    }
+
+    private ResponseEntity<?> downloadDocument(ApiClient client, Map<String, Object> data)
+            throws SignNowApiException, IOException {
+        String documentId = (String) data.get("document_id");
+
+        DocumentDownloadGetRequest req = new DocumentDownloadGetRequest();
+        req.withDocumentId(documentId).withType("collapsed");
+        DocumentDownloadGetResponse resp = (DocumentDownloadGetResponse) client.send(req).getResponse();
+
+        File file = resp.getFile();
+        byte[] content = Files.readAllBytes(file.toPath());
+        file.delete();
+
+        return ResponseEntity.ok()
+                .header("Content-Type", "application/pdf")
+                .header("Content-Disposition", "attachment; filename=\"final_document.pdf\"")
+                .body(content);
+    }
+}
diff --git a/src/main/java/com/signnow/samples/UploadEmbeddedSender/IndexController.java b/src/main/java/com/signnow/samples/UploadEmbeddedSender/IndexController.java
index 42ee12c..3c3ad8c 100644
--- a/src/main/java/com/signnow/samples/UploadEmbeddedSender/IndexController.java
+++ b/src/main/java/com/signnow/samples/UploadEmbeddedSender/IndexController.java
@@ -20,6 +20,7 @@
 import com.signnow.core.ApiClient;
 import com.signnow.core.exception.SignNowApiException;
 import com.signnow.javasampleapp.ExampleInterface;
+import com.signnow.javasampleapp.config.AppConfig;
 import org.springframework.http.ResponseEntity;
 import org.springframework.stereotype.Controller;
 
@@ -143,7 +144,7 @@ private Map<String, Object> createDocumentGroup(ApiClient client, String documen
 
     private Map<String, Object> createEmbeddedSendingUrl(ApiClient client, String documentGroupId) throws SignNowApiException {
         // Return URL after embedded sending to redirect to status page
-        String redirectUrl = "http://localhost:8080/samples/UploadEmbeddedSender?" +
+        String redirectUrl = AppConfig.sampleUrl("UploadEmbeddedSender") + "?" +
                 "page=status-page&document_group_id=" + documentGroupId;
 
         DocumentGroupEmbeddedSendingLinkPostRequest embeddedSendingRequest = new DocumentGroupEmbeddedSendingLinkPostRequest(
diff --git a/src/main/resources/application.properties b/src/main/resources/application.properties
index 0379837..a13a71e 100644
--- a/src/main/resources/application.properties
+++ b/src/main/resources/application.properties
@@ -1,3 +1,17 @@
 spring.application.name=java-sample-app
+server.port=${PORT:8080}
 server.error.whitelabel.enabled=false
-signnow.api.signer_email=test@example.com
+
+# App configuration
+app.base-url=${APP_BASE_URL:http://localhost:8080}
+signnow.api.signer_email=${SIGNNOW_SIGNER_EMAIL:test@example.com}
+signnow.api.demo_user_email=${SIGNNOW_DEMO_USER_EMAIL:example@example.com}
+signnow.api.demo_user_password=${SIGNNOW_DEMO_USER_PASSWORD:example}
+
+# Actuator - restrict to health/info only
+management.endpoints.web.exposure.include=health,info
+management.endpoint.health.show-details=never
+
+# Logging
+logging.level.com.signnow=INFO
+logging.pattern.level=%5p [%X{traceId:-},%X{spanId:-}]
diff --git a/src/main/resources/static/samples/EVDemoSendingAnd3EmbeddedSigners/index.html b/src/main/resources/static/samples/EVDemoSendingAnd3EmbeddedSigners/index.html
new file mode 100644
index 0000000..61c66fd
--- /dev/null
+++ b/src/main/resources/static/samples/EVDemoSendingAnd3EmbeddedSigners/index.html
@@ -0,0 +1,265 @@
+<!doctype html>
+<html class="no-js" lang="">
+
+<head>
+    <meta charset="utf-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1">
+    <title>EVDemoSendingAnd3EmbeddedSigners</title>
+    <link href="/css/bootstrap.min.css" rel="stylesheet">
+    <link href="https://fonts.googleapis.com/css?family=Open+Sans:300,400,600,700" rel="stylesheet" />
+    <link rel="stylesheet" href="/css/styles.css">
+    <meta name="description" content="SignNow EVDemoSendingAnd3EmbeddedSigners">
+    <link rel="icon" href="/favicon.ico" sizes="any">
+    <link rel="icon" href="/icon.svg" type="image/svg+xml">
+    <link rel="apple-touch-icon" href="/icon.png">
+    <meta name="theme-color" content="#fafafa">
+</head>
+
+<body>
+
+<div class="header">
+    <img src="/img/sign-now.png" alt="SignNow Logo">
+</div>
+
+<!-- 1) Initial Form Container -->
+<div id="form-container" style="display:none">
+    <h4 class="mb-3">Enter Agent and Signers Information</h4>
+    <form id="startWorkflowForm" action="#" method="post">
+        <div class="sn-input-group mb-2">
+            <label for="agent_name">Agent Name <span class="text-danger">*</span></label>
+            <input type="text" id="agent_name" name="agent_name" required placeholder="e.g. Jane Doe">
+        </div>
+        <div class="sn-input-group mb-2">
+            <label for="agent_email">Agent Email <span class="text-danger">*</span></label>
+            <input type="email" id="agent_email" name="agent_email" required placeholder="e.g. agent@example.com">
+        </div>
+
+        <div class="sn-input-group mb-2">
+            <label for="signer1_name">Signer 1 Name <span class="text-danger">*</span></label>
+            <input type="text" id="signer1_name" name="signer1_name" required placeholder="e.g. John Smith">
+        </div>
+        <div class="sn-input-group mb-2">
+            <label for="signer1_email">Signer 1 Email <span class="text-danger">*</span></label>
+            <input type="email" id="signer1_email" name="signer1_email" required placeholder="e.g. signer1@example.com">
+        </div>
+
+        <div class="sn-input-group mb-2">
+            <label for="signer2_name">Signer 2 Name <span class="text-danger">*</span></label>
+            <input type="text" id="signer2_name" name="signer2_name" required placeholder="e.g. Sarah Brown">
+        </div>
+        <div class="sn-input-group mb-4">
+            <label for="signer2_email">Signer 2 Email <span class="text-danger">*</span></label>
+            <input type="email" id="signer2_email" name="signer2_email" required placeholder="e.g. signer2@example.com">
+        </div>
+
+        <button type="submit" class="button-primary" id="startWorkflowBtn">Continue</button>
+        <button class="btn btn-dark d-none" id="loadingBtnStart" type="button" disabled>
+            <span class="spinner-border spinner-border-sm" role="status" aria-hidden="true"></span>
+            Loading...
+        </button>
+    </form>
+</div>
+
+<!-- 2) Signing Step Container -->
+<div id="signing-container" style="display:none">
+    <div class="thank-you-message text-center">
+        <h4 id="signing-title" class="mb-3"></h4>
+        <p id="signing-instructions" class="mb-3"></p>
+        <button class="btn btn-dark d-none" id="loadingBtnSigning" type="button" disabled>
+            <span class="spinner-border spinner-border-sm" role="status" aria-hidden="true"></span>
+            Loading signing session...
+        </button>
+    </div>
+</div>
+
+<!-- 3) Final Step Container -->
+<div id="finish-container" style="display:none">
+    <div class="thank-you-message text-center">
+        <img src="/img/doc-completed.png" alt="signNow" class="mb-3" />
+        <h4>You've filled out and signed a document</h4>
+        <p class="mb-4">A copy was also sent to your inbox and saved to your SignNow account.</p>
+        <button id="downloadBtn" class="button-secondary">Download Document</button>
+    </div>
+</div>
+
+<div class="copyright gray--700 mt-3">Copyright (c) 2025 airSlate, Inc., SignNow API Sample Application v3.0</div>
+
+<script>
+document.addEventListener('DOMContentLoaded', main);
+
+async function main() {
+    const pagesMap = {
+        start   : showStartForm,
+        agent   : showSigningPrompt,
+        signer1 : showSigningPrompt,
+        signer2 : showSigningPrompt,
+        finish  : showFinishPage
+    };
+
+    const urlParams = new URLSearchParams(window.location.search);
+    const step      = urlParams.get('step') || 'start';
+
+    hideAllContainers();
+    if (pagesMap[step]) {
+        await pagesMap[step](step);
+    } else {
+        await showStartForm();
+    }
+}
+
+function hideAllContainers() {
+    document.querySelectorAll('#form-container, #signing-container, #finish-container')
+        .forEach(el => el.style.display = 'none');
+}
+
+function showStartForm() {
+    const formContainer     = document.getElementById('form-container');
+    const startWorkflowForm = document.getElementById('startWorkflowForm');
+    const startBtn          = document.getElementById('startWorkflowBtn');
+    const loadingBtn        = document.getElementById('loadingBtnStart');
+
+    formContainer.style.display = 'block';
+
+    startWorkflowForm.addEventListener('submit', async (evt) => {
+        evt.preventDefault();
+        startBtn.classList.add('d-none');
+        loadingBtn.classList.remove('d-none');
+
+        const agent_name    = document.getElementById('agent_name').value;
+        const agent_email   = document.getElementById('agent_email').value;
+        const signer1_name  = document.getElementById('signer1_name').value;
+        const signer1_email = document.getElementById('signer1_email').value;
+        const signer2_name  = document.getElementById('signer2_name').value;
+        const signer2_email = document.getElementById('signer2_email').value;
+
+        try {
+            const response = await fetch('/api/samples/EVDemoSendingAnd3EmbeddedSigners', {
+                method : 'POST',
+                headers: { 'Content-Type': 'application/json' },
+                body   : JSON.stringify({
+                    action: 'start-workflow',
+                    agent_name, agent_email,
+                    signer1_name, signer1_email,
+                    signer2_name, signer2_email
+                })
+            });
+
+            if (!response.ok) throw new Error('Server error when starting workflow.');
+
+            const data = await response.json();
+            if (!data.document_id || !data.embedded_link) {
+                throw new Error('Missing "document_id" or "embedded_link" in response.');
+            }
+
+            const nextUrl = new URL(window.location.href);
+            nextUrl.searchParams.set('step', 'agent');
+            nextUrl.searchParams.set('document_id', data.document_id);
+            nextUrl.searchParams.set('embedded_link', data.embedded_link);
+            window.location.href = nextUrl.toString();
+        } catch (err) {
+            alert(err.message || 'Could not start workflow.');
+            startBtn.classList.remove('d-none');
+            loadingBtn.classList.add('d-none');
+        }
+    });
+}
+
+async function showSigningPrompt(step) {
+    const signingContainer    = document.getElementById('signing-container');
+    const signingTitle        = document.getElementById('signing-title');
+    const signingInstructions = document.getElementById('signing-instructions');
+    const loadingBtnSigning   = document.getElementById('loadingBtnSigning');
+
+    signingContainer.style.display = 'block';
+
+    const roleMap = {
+        agent   : { displayName: 'Agent',    roleName: 'Contract Preparer' },
+        signer1 : { displayName: 'Signer 1', roleName: 'Recipient 1' },
+        signer2 : { displayName: 'Signer 2', roleName: 'Recipient 2' }
+    };
+
+    const urlParams   = new URLSearchParams(window.location.search);
+    const documentId  = urlParams.get('document_id');
+    const embeddedLink = urlParams.get('embedded_link');
+    const thisRole    = roleMap[step];
+
+    if (!documentId) {
+        signingTitle.textContent        = 'Document ID Not Found';
+        signingInstructions.textContent = 'Cannot start signing. Missing document reference.';
+        return;
+    }
+
+    signingTitle.textContent = `Start Signing as ${thisRole.displayName}`;
+
+    let signingLink = embeddedLink || '';
+    if (!signingLink && (step === 'signer1' || step === 'signer2')) {
+        loadingBtnSigning.classList.remove('d-none');
+        try {
+            const response = await fetch('/api/samples/EVDemoSendingAnd3EmbeddedSigners', {
+                method : 'POST',
+                headers: { 'Content-Type': 'application/json' },
+                body   : JSON.stringify({
+                    action     : 'next-signer',
+                    document_id: documentId,
+                    roleName   : thisRole.roleName
+                })
+            });
+            if (!response.ok) throw new Error('Server failed to create next-signer link');
+            const data = await response.json();
+            if (!data.embedded_link) throw new Error('Missing embedded_link in response');
+            signingLink = data.embedded_link;
+        } catch (err) {
+            signingTitle.textContent        = 'Error Getting Signing Link';
+            signingInstructions.textContent = err.message;
+            loadingBtnSigning.classList.add('d-none');
+            return;
+        }
+        loadingBtnSigning.classList.add('d-none');
+    }
+
+    if (signingLink) {
+        window.location.href = signingLink;
+    } else {
+        alert('No embedded signing link available for this role.');
+    }
+}
+
+function showFinishPage() {
+    const finishContainer = document.getElementById('finish-container');
+    finishContainer.style.display = 'block';
+
+    const urlParams  = new URLSearchParams(window.location.search);
+    const documentId = urlParams.get('document_id');
+    const downloadBtn = document.getElementById('downloadBtn');
+
+    try { parent.postMessage({ type: 'SAMPLE_APP_FINISHED' }, window.origin); } catch (e) {}
+
+    downloadBtn.onclick = async () => {
+        if (!documentId) {
+            alert('No document ID found, unable to download.');
+            return;
+        }
+        try {
+            const response = await fetch('/api/samples/EVDemoSendingAnd3EmbeddedSigners', {
+                method : 'POST',
+                headers: { 'Content-Type': 'application/json' },
+                body   : JSON.stringify({ action: 'download', document_id: documentId })
+            });
+            if (!response.ok) throw new Error('Download request failed.');
+
+            const filename = response.headers.get('Content-Disposition')?.match(/filename="([^"]+)"/)?.[1] || 'signed-document.pdf';
+            const blob = await response.blob();
+            const url  = window.URL.createObjectURL(blob);
+            const link = document.createElement('a');
+            link.href     = url;
+            link.download = filename;
+            link.click();
+            window.URL.revokeObjectURL(url);
+        } catch (error) {
+            alert(`Document download error: ${error.message}`);
+        }
+    };
+}
+</script>
+</body>
+</html>
diff --git a/src/main/resources/static/samples/EmbeddedSenderWithFormAndFirstSigner/index.html b/src/main/resources/static/samples/EmbeddedSenderWithFormAndFirstSigner/index.html
index 8755d97..b30f0b7 100644
--- a/src/main/resources/static/samples/EmbeddedSenderWithFormAndFirstSigner/index.html
+++ b/src/main/resources/static/samples/EmbeddedSenderWithFormAndFirstSigner/index.html
@@ -166,18 +166,16 @@ <h4>No signers found</h4>
                 // Redirect to signing URL
                 window.location.href = result.signing_url;
             } else {
-                signingContent.innerHTML = `
-                        <div class="alert alert-danger">
-                            Error: ${result.message || 'Failed to create signing URL'}
-                        </div>
-                    `;
+                const errorDiv = document.createElement('div');
+                errorDiv.className = 'alert alert-danger';
+                errorDiv.textContent = 'Error: ' + (result.message || 'Failed to create signing URL');
+                signingContent.replaceChildren(errorDiv);
             }
         } catch (error) {
-            signingContent.innerHTML = `
-                    <div class="alert alert-danger">
-                        Error: ${error.message}
-                    </div>
-                `;
+            const errorDiv = document.createElement('div');
+            errorDiv.className = 'alert alert-danger';
+            errorDiv.textContent = 'Error: ' + error.message;
+            signingContent.replaceChildren(errorDiv);
         }
     }
 
diff --git a/src/main/resources/static/samples/UploadEmbeddedEditingAndInvite/index.html b/src/main/resources/static/samples/UploadEmbeddedEditingAndInvite/index.html
new file mode 100644
index 0000000..69a201a
--- /dev/null
+++ b/src/main/resources/static/samples/UploadEmbeddedEditingAndInvite/index.html
@@ -0,0 +1,300 @@
+<!doctype html>
+<html lang="en">
+<head>
+    <meta charset="UTF-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1.0">
+    <title>Upload Embedded Editing and Invite - SignNow Sample</title>
+    <link href="/css/bootstrap.min.css" rel="stylesheet">
+    <link href="/css/styles.css" rel="stylesheet">
+    <link href="https://fonts.googleapis.com/css2?family=Open+Sans:wght@400;600&display=swap" rel="stylesheet">
+</head>
+<body>
+    <div class="header">
+        <img src="/img/sign-now.png" alt="SignNow Logo">
+    </div>
+
+    <!-- Upload Page -->
+    <div id="upload-page" class="container-block">
+        <h4>Upload Document for Editing and Signing</h4>
+        <p>This sample uploads a pre-loaded PDF to SignNow, creates an embedded editing link, and sends an invite for signing.</p>
+
+        <button class="button-primary" id="upload-btn">Upload Document</button>
+        <button class="btn btn-dark d-none" id="loading-upload-btn" type="button" disabled>
+            <span class="spinner-border spinner-border-sm" role="status" aria-hidden="true"></span>
+            Uploading...
+        </button>
+
+        <div id="upload-result" class="mt-3" style="display: none;">
+            <div class="alert alert-success">
+                <strong>Success!</strong> Document uploaded successfully. Opening editor...
+            </div>
+            <div class="text-center">
+                <button class="button-primary" id="proceed-to-edit-btn">Open Document Editor</button>
+            </div>
+        </div>
+    </div>
+
+    <!-- Invite Page -->
+    <div id="invite-page" class="container-block" style="display: none;">
+        <h4>Send Signing Invite</h4>
+        <p>Document has been edited successfully. Now you can send an invite to a signer to complete the document.</p>
+
+        <form id="invite-form">
+            <div class="sn-input-group mb-3">
+                <label for="signer_name">Signer Name <span class="text-danger">*</span></label>
+                <input type="text" id="signer_name" name="signer_name" placeholder="Enter signer name" required>
+            </div>
+            <div class="sn-input-group mb-3">
+                <label for="signer_email">Signer Email <span class="text-danger">*</span></label>
+                <input type="email" id="signer_email" name="signer_email" placeholder="Enter signer email" required>
+            </div>
+            <button type="submit" class="button-primary" id="send-invite-btn">Send Signing Invite</button>
+            <button class="btn btn-dark d-none" id="loading-invite-btn" type="button" disabled>
+                <span class="spinner-border spinner-border-sm" role="status" aria-hidden="true"></span>
+                Sending invite...
+            </button>
+        </form>
+    </div>
+
+    <!-- Status Page -->
+    <div id="status-page" class="container-block" style="display: none;">
+        <h4>Document Status &amp; Final Document</h4>
+        <p>You can check signing status and download the completed document here.</p>
+
+        <div id="no-recipients-container" class="no-recipients" style="display: none;">
+            <div class="thank-you-message">
+                <h4>No signers found</h4>
+                <p class="mb-4">No signers have been added to this document yet.</p>
+            </div>
+        </div>
+
+        <ul class="status-list" id="documentList"></ul>
+    </div>
+
+    <div class="copyright gray--700 mt-3">Copyright (c) 2025 airSlate, Inc., SignNow API Sample Application v3.0</div>
+
+    <script>
+        function getQueryParam(key) {
+            return new URLSearchParams(window.location.search).get(key) || '';
+        }
+
+        async function handlePages(pagesMap, defaultKey) {
+            const fallbackKey = defaultKey || Object.keys(pagesMap)[0];
+            const pageParam = getQueryParam('page') || fallbackKey;
+
+            Object.keys(pagesMap).forEach(id => {
+                const el = document.getElementById(id);
+                if (el) el.style.display = 'none';
+            });
+
+            const handlerKey = pagesMap[pageParam] ? pageParam : fallbackKey;
+            const el = document.getElementById(handlerKey);
+            if (el) el.style.display = 'block';
+            if (typeof pagesMap[handlerKey] === 'function') {
+                await pagesMap[handlerKey](el);
+            }
+        }
+
+        async function initUploadPage() {
+            const uploadBtn  = document.getElementById('upload-btn');
+            const loadingBtn = document.getElementById('loading-upload-btn');
+            const uploadResult = document.getElementById('upload-result');
+            const proceedBtn = document.getElementById('proceed-to-edit-btn');
+
+            const documentId = getQueryParam('document_id');
+            if (documentId) {
+                uploadResult.style.display = 'block';
+            }
+
+            uploadBtn.addEventListener('click', async () => {
+                uploadBtn.classList.add('d-none');
+                loadingBtn.classList.remove('d-none');
+
+                try {
+                    const uploadResp = await fetch('/api/samples/UploadEmbeddedEditingAndInvite', {
+                        method : 'POST',
+                        headers: { 'Content-Type': 'application/json' },
+                        body   : JSON.stringify({ action: 'upload_and_create_dg' })
+                    });
+                    const uploadResult = await uploadResp.json();
+                    if (!uploadResult.success) throw new Error(uploadResult.message || 'Upload failed');
+
+                    const editResp = await fetch('/api/samples/UploadEmbeddedEditingAndInvite', {
+                        method : 'POST',
+                        headers: { 'Content-Type': 'application/json' },
+                        body   : JSON.stringify({ action: 'create_embedded_edit', document_id: uploadResult.document_id })
+                    });
+                    const editResult = await editResp.json();
+                    if (!editResult.success) throw new Error(editResult.message || 'Failed to create editor link');
+
+                    window.location.href = editResult.edit_link;
+                } catch (err) {
+                    alert('Error: ' + err.message);
+                    uploadBtn.classList.remove('d-none');
+                    loadingBtn.classList.add('d-none');
+                }
+            });
+
+            proceedBtn.addEventListener('click', async () => {
+                const docId = getQueryParam('document_id');
+                try {
+                    const resp = await fetch('/api/samples/UploadEmbeddedEditingAndInvite', {
+                        method : 'POST',
+                        headers: { 'Content-Type': 'application/json' },
+                        body   : JSON.stringify({ action: 'create_embedded_edit', document_id: docId })
+                    });
+                    const result = await resp.json();
+                    if (result.success) {
+                        window.location.href = result.edit_link;
+                    } else {
+                        alert('Error: ' + (result.message || 'Failed to create embedded edit link'));
+                    }
+                } catch (err) {
+                    alert('Error: ' + err.message);
+                }
+            });
+        }
+
+        async function initInvitePage() {
+            const documentId = getQueryParam('document_id');
+            if (!documentId) {
+                document.getElementById('invite-page').innerHTML = '<p>No Document ID found. Please start over.</p>';
+                return;
+            }
+
+            const form        = document.getElementById('invite-form');
+            const sendBtn     = document.getElementById('send-invite-btn');
+            const loadingBtn  = document.getElementById('loading-invite-btn');
+
+            form.addEventListener('submit', async (event) => {
+                event.preventDefault();
+                sendBtn.classList.add('d-none');
+                loadingBtn.classList.remove('d-none');
+
+                const signerName  = document.getElementById('signer_name').value.trim();
+                const signerEmail = document.getElementById('signer_email').value.trim();
+
+                try {
+                    const response = await fetch('/api/samples/UploadEmbeddedEditingAndInvite', {
+                        method : 'POST',
+                        headers: { 'Content-Type': 'application/json' },
+                        body   : JSON.stringify({
+                            action      : 'create_invite',
+                            document_id : documentId,
+                            signer_name : signerName,
+                            signer_email: signerEmail
+                        })
+                    });
+                    const result = await response.json();
+                    if (result.success) {
+                        window.location.href = '/samples/UploadEmbeddedEditingAndInvite?page=status-page&document_id=' + documentId;
+                    } else {
+                        throw new Error(result.message || 'Failed to send invite');
+                    }
+                } catch (err) {
+                    alert('Error: ' + err.message);
+                    sendBtn.classList.remove('d-none');
+                    loadingBtn.classList.add('d-none');
+                }
+            });
+        }
+
+        async function initStatusPage() {
+            try { parent.postMessage({ type: 'SAMPLE_APP_FINISHED' }, location.origin); } catch (e) {}
+
+            const documentId = getQueryParam('document_id');
+            if (!documentId) {
+                document.getElementById('status-page').innerHTML = '<p>No Document ID provided.</p>';
+                return;
+            }
+
+            const documentList = document.getElementById('documentList');
+            const noRecipientsContainer = document.getElementById('no-recipients-container');
+
+            async function updateStatuses() {
+                try {
+                    const response = await fetch('/api/samples/UploadEmbeddedEditingAndInvite', {
+                        method : 'POST',
+                        headers: { 'Content-Type': 'application/json' },
+                        body   : JSON.stringify({ action: 'invite-status', document_id: documentId })
+                    });
+                    if (!response.ok) throw new Error('Failed to fetch invite statuses.');
+
+                    const data = await response.json();
+                    documentList.innerHTML = '';
+                    noRecipientsContainer.style.display = 'none';
+
+                    if (Array.isArray(data) && data.length > 0) {
+                        data.forEach(doc => {
+                            const li = document.createElement('li');
+                            li.className = 'status-item';
+                            li.innerHTML = `
+                                <div class="status-wrapper">
+                                    <div class="status-info">
+                                        <strong>${doc.name}</strong>
+                                        <span class="status-date">${doc.timestamp || ''}</span>
+                                    </div>
+                                </div>
+                                <div class="status-container">
+                                    <div class="status-badge">&#9679; <span>${doc.status}</span></div>
+                                </div>
+                                <div>
+                                    <button class="button-outlined download-document">Download Document</button>
+                                    <button class="button-outlined refresh-status">Refresh</button>
+                                    <button class="btn btn-dark d-none loading-button" type="button" disabled>
+                                        <span class="spinner-border spinner-border-sm" role="status" aria-hidden="true"></span>
+                                        Refresh
+                                    </button>
+                                </div>
+                            `;
+
+                            li.querySelector('.download-document').addEventListener('click', async () => {
+                                const res = await fetch('/api/samples/UploadEmbeddedEditingAndInvite', {
+                                    method : 'POST',
+                                    headers: { 'Content-Type': 'application/json' },
+                                    body   : JSON.stringify({ document_id: documentId, action: 'download-document' })
+                                });
+                                if (!res.ok) throw new Error('Download failed');
+                                const blob = await res.blob();
+                                const url  = window.URL.createObjectURL(blob);
+                                Object.assign(document.createElement('a'), { href: url, download: 'document.pdf' }).click();
+                                window.URL.revokeObjectURL(url);
+                            });
+
+                            li.querySelector('.refresh-status').addEventListener('click', async () => {
+                                const refreshBtn  = li.querySelector('.refresh-status');
+                                const loadingBtn  = li.querySelector('.loading-button');
+                                refreshBtn.classList.add('d-none');
+                                loadingBtn.classList.remove('d-none');
+                                try {
+                                    await updateStatuses();
+                                } finally {
+                                    refreshBtn.classList.remove('d-none');
+                                    loadingBtn.classList.add('d-none');
+                                }
+                            });
+
+                            documentList.appendChild(li);
+                        });
+                    } else {
+                        noRecipientsContainer.style.display = 'block';
+                    }
+                } catch (err) {
+                    console.error(err);
+                    alert('Something went wrong while updating statuses.');
+                }
+            }
+
+            await updateStatuses();
+        }
+
+        document.addEventListener('DOMContentLoaded', async () => {
+            await handlePages({
+                'upload-page': initUploadPage,
+                'invite-page': initInvitePage,
+                'status-page': initStatusPage
+            }, 'upload-page');
+        });
+    </script>
+</body>
+</html>
diff --git a/src/main/resources/static/samples/UploadEmbeddedSender/index.html b/src/main/resources/static/samples/UploadEmbeddedSender/index.html
index ec95746..39ddb91 100644
--- a/src/main/resources/static/samples/UploadEmbeddedSender/index.html
+++ b/src/main/resources/static/samples/UploadEmbeddedSender/index.html
@@ -91,18 +91,16 @@ <h4>No signers found</h4>
                 // Redirect to embedded sending URL
                 window.location.href = result.embedded_url;
             } else {
-                uploadContent.innerHTML = `
-                        <div class="alert alert-danger">
-                            Error: ${result.message || 'Failed to upload document and create embedded sending link'}
-                        </div>
-                    `;
+                const errorDiv = document.createElement('div');
+                errorDiv.className = 'alert alert-danger';
+                errorDiv.textContent = 'Error: ' + (result.message || 'Failed to upload document and create embedded sending link');
+                uploadContent.replaceChildren(errorDiv);
             }
         } catch (error) {
-            uploadContent.innerHTML = `
-                    <div class="alert alert-danger">
-                        Error: ${error.message}
-                    </div>
-                `;
+            const errorDiv = document.createElement('div');
+            errorDiv.className = 'alert alert-danger';
+            errorDiv.textContent = 'Error: ' + error.message;
+            uploadContent.replaceChildren(errorDiv);
             console.error(error);
         }
     }
diff --git a/src/main/resources/views/index.html b/src/main/resources/views/index.html
index c676ca0..d762440 100644
--- a/src/main/resources/views/index.html
+++ b/src/main/resources/views/index.html
@@ -2,7 +2,7 @@
 <html lang="en">
   <head>
     <meta charset="UTF-8" />
-    <link rel="icon" type="image/x-icon" href="{{ secure_asset('favicon.ico') }}" />
+    <link rel="icon" type="image/x-icon" href="/favicon.ico" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
     <link href="https://fonts.googleapis.com/css?family=Open+Sans:300,400,600,700" rel="stylesheet" />
     <title>Sample Apps</title>
diff --git a/src/test/java/com/signnow/javasampleapp/controllers/RoutingControllerTest.java b/src/test/java/com/signnow/javasampleapp/controllers/RoutingControllerTest.java
new file mode 100644
index 0000000..eb4efa8
--- /dev/null
+++ b/src/test/java/com/signnow/javasampleapp/controllers/RoutingControllerTest.java
@@ -0,0 +1,51 @@
+package com.signnow.javasampleapp.controllers;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
+import org.springframework.test.web.servlet.MockMvc;
+
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.post;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+@WebMvcTest(controllers = {RoutingController.class, GlobalExceptionHandler.class})
+class RoutingControllerTest {
+
+    @Autowired
+    MockMvc mvc;
+
+    @Test
+    void root_returns404ErrorPage() throws Exception {
+        mvc.perform(get("/"))
+                .andExpect(status().isNotFound())
+                .andExpect(content().contentTypeCompatibleWith("text/html"));
+    }
+
+    @Test
+    void getExample_withInvalidName_returns404() throws Exception {
+        mvc.perform(get("/samples/has-dash"))
+                .andExpect(status().isNotFound());
+    }
+
+    @Test
+    void getExample_withPathTraversal_returns404() throws Exception {
+        mvc.perform(get("/samples/..%2Fevil"))
+                .andExpect(status().isNotFound());
+    }
+
+    @Test
+    void getExample_withUnknownButValidName_returns404() throws Exception {
+        mvc.perform(get("/samples/NoSuchSample_xyz"))
+                .andExpect(status().isNotFound());
+    }
+
+    @Test
+    void postExample_withInvalidName_returns404() throws Exception {
+        mvc.perform(post("/api/samples/bad-name")
+                        .contentType("application/json")
+                        .content("{}"))
+                .andExpect(status().isNotFound());
+    }
+}