Ishiki (石記)

Study your Anki flashcards from your wrist on a Pebble Core Time 2 (emery, 200×228, 64-color, 4 buttons). Pick a deck, read the front, reveal the back, grade it, move on — backed by your real collection.

The backend is local: an Android companion app reads and writes your on-device AnkiDroid collection and serves the watch over localhost. AnkiDroid does the AnkiWeb sync itself, so nothing here ever logs into AnkiWeb or touches its (private) sync protocol.

AnkiWeb ⇄ AnkiDroid ⇄ (ContentProvider) Ishiki companion ⇄ (localhost:8765) PebbleKit JS ⇄ (Bluetooth) watch

On the watch

• Deck list — Up/Down to move, Select to open. Due counts refresh each time the list is shown (so they reflect what you just reviewed).
• Front — Up/Down scroll a long question · Select reveals the answer.
• Back — a colored action bar on the right edge aligned to the buttons:
  • Up = ✓ Good (green) · Select = ~ Hard (yellow) · Down = ✗ Again (red)
  • The screen flashes the grade's color, then the next card loads.
  • Hold Up/Down to scroll a long answer.
• If the watch can't reach the companion (Bluetooth down, app closed, AnkiDroid busy), it vibrates instead of hanging.

Reviews are store-and-forward: a deck's due cards are fetched as a batch and queued reviews (with timestamps) are flushed to the companion as it becomes reachable.

Repo layout

companion/   Android companion app (Kotlin) — the current backend
pebble/      Pebble watchapp (C) + PebbleKit JS bridge
backend/     legacy Python AnkiWeb proxy (alternative — see below)
versions     per-app versions, read by bump.sh
bump.sh      set versions + rebuild both artifacts
.github/workflows/release.yml   CI: build + publish the signed companion APK on a version bump
CHANGELOG.md   companion app changelog (watch app: pebble/CHANGELOG.md)
CLAUDE.md    full dev / handoff notes

Companion app (Android)

Kotlin, minimal UI, a foreground service running NanoHTTPD on 127.0.0.1:8765 over AnkiDroid's ContentProvider:

Method	Path	Returns
GET	/decks	[{id, name, due}]
GET	/cards?deckId=<id>	[{id:"noteId:ord", front, back}]
POST	/review {cardId, ease, timestamp}	{ok:true} — ease 1=Again, 2=Hard, 3=Good

Build / install:

cd companion
./gradlew assembleDebug      # -> app/build/outputs/apk/debug/app-debug.apk

Or grab the APK from Releases. Install it, open it once, and grant the AnkiDroid permission + notifications. Requires AnkiDroid installed and signed into your AnkiWeb account. See companion/README.md for details and limitations.

Watch app (Pebble)

cd pebble
pebble build                 # -> build/pebble.pbw   (needs the Pebble SDK; see CLAUDE.md)

Sideload pebble.pbw with the Pebble (Core Devices) app (Android: file manager or Rebble's Sideload Helper; iOS: the Pebble Core share sheet). Then open the app's Settings on the phone and set Backend URL = http://127.0.0.1:8765 (leave the token blank — the companion is local and unauthenticated).

Releases & versioning

The two apps version independently in versions:

companion=0.2.0
pebble=0.2.0

bump.sh applies them and rebuilds both:

./bump.sh                    # apply versions/ and rebuild both
./bump.sh companion 0.3.0    # set companion's version, then apply + rebuild
./bump.sh pebble 1.1.0       # set pebble's version, then apply + rebuild

Pushing to main triggers the release workflow: when the companion version is one that hasn't been released yet, it builds the APK and publishes a v<version> GitHub Release. With the signing secrets set (KEYSTORE_B64, KEYSTORE_PASSWORD, KEY_ALIAS, KEY_PASSWORD) the APK is release-signed; otherwise it falls back to a debug build.

Limitations

• The companion's AnkiDroid calls (deck query, card columns, review update) are AnkiDroid-version-sensitive and not yet verified on a physical device.
• No backdating — AnkiDroid records a review at submit time; same-day reviews are fine (Anki intervals are day-granular), only reviews queued across midnight can drift.
• On the answer screen single-press grades; hold Up/Down to scroll a long answer.

Legacy: Python AnkiWeb proxy (backend/)

Before the companion, the backend was a Python/FastAPI service that synced AnkiWeb directly with the official anki library and exposed /decks /next /answer /sync. It still works (Dockerized, background auto-sync) and is kept as an alternative for setups without AnkiDroid, but the on-device companion is the recommended path (no AnkiWeb credentials, no reverse-engineered protocol, no server to host). Setup is in backend/ and the rationale is in CLAUDE.md.