# bincio-rec

GPS activity recorder for the bincio ecosystem.
Companion to **bincio-autarchive** (archive/sync app): rec makes the data, autarchive stores and syncs it.

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## Concept

A focused, minimal recording app for cycling, running, hiking, and walking.
Records GPS track + BLE sensor data, saves to GPX, optionally uploads directly to a bincio-activity server.
Future: live navigation / turn-by-turn instructions.

The app does one thing well: **record**. No browsing, no analysis — that's autarchive's job.

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## Ecosystem

```
bincio-rec          →  writes GPX files to shared storage
bincio-autarchive   →  imports GPX, stores locally, syncs to server
bincio-activity     →  server: parses GPX, stores activities, serves API
bincio-auth         →  auth service: issues JWTs for all bincio apps
```

bincio-rec can also upload directly to bincio-activity via `/api/upload/raw` (same endpoint autarchive uses), with instance URL + API token configured in settings.

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## Tech Stack

**Expo Prebuild** (not managed Expo, not bare RN).

- Managed Expo ruled out: BLE requires native modules
- Bare RN ruled out: Expo library ecosystem is valuable (location, notifications, file system)
- Prebuild gives full native access while keeping Expo tooling and EAS Build

Key libraries:
- `expo-location` + `expo-task-manager` — background GPS recording
- `react-native-ble-plx` — BLE sensors (HR, power, cadence)
- `@maplibre/maplibre-react-native` — live track map, future navigation
- `expo-notifications` — km milestone alerts, future navigation cues
- `expo-keep-awake` — keep screen on during recording (user-toggleable)
- `expo-file-system` — write GPX/JSON to shared storage
- `expo-sqlite` — local DB for past recordings list

Target: **Android first**, iOS second.

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## v1 Screens

1. **Sensor pairing** — scan BLE, pair HR monitor / power meter / cadence sensor; persisted
2. **Recording** — start / pause / resume / stop
   - Live stats: elapsed time, distance, current+avg speed, HR, power, cadence, elevation gain
   - Map with track drawn in real time
   - Keep-awake toggle
3. **Post-recording summary** — stats overview, title field, save / discard
4. **Saved recordings** — list of past sessions; tap to export GPX or upload to server
5. **Settings** — bincio instance URL + API token; km notification toggle; upload format

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## Output Format

**GPX with Garmin trackpoint extensions** — one `<trkpt>` per second with:
- lat/lon/elevation from GPS
- `<gpxtpx:hr>` — heart rate
- `<gpxtpx:power>` — power (watts)
- `<gpxtpx:cad>` — cadence (rpm)

bincio-activity already parses this format via `bincio.extract.parsers`.

Files saved to a user-accessible location (iOS Files app / Android shared storage) so bincio-autarchive can import them manually.

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## Known Platform Concerns

- **Android battery optimization**: aggressive OEMs (Xiaomi, Samsung, Huawei) kill background tasks. Prompt user to whitelist bincio-rec in battery settings on first launch. Every recording app has this problem — no framework-level fix.
- **iOS background location**: requires `location` background mode in `Info.plist` and "Always" location permission. Fine for sideloading/TestFlight; App Store submission requires clear justification.
- **iOS foreground notifications**: notification sounds are suppressed when app is in foreground — use `expo-av` audio cue instead for km alerts while screen is on.

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## Out of Scope (v1)

- Navigation / turn-by-turn routing
- Auto-pause (stop lights, etc.)
- Structured workouts / intervals
- Offline maps
- Live tracking / sharing