ImuaTrak
Imua — Hawaiian for "charge forward".
Outrigger canoe paddling fitness app for iPhone and Android (with watch
support arriving in Phase 2). Records GPS, heart rate, stroke rate, splits,
weather, and audio-detected side switches ("huts") for OC1, OC2, OC6, V1,
SUP, and surfski sessions. Sessions sync to Firebase, export to Android
Health Connect, and export to GPX/FIT for upload to Strava, Garmin
Connect, etc.
Stack
- Expo SDK 53 + React Native + TypeScript
- expo-router for file-system routing
- Firebase JS SDK (Auth, Firestore, Storage, Functions)
- expo-location + expo-task-manager for background GPS
- expo-sensors for accelerometer-based stroke detection
- react-native-health + react-native-health-connect for native health stores
- react-native-maps for the route map
Repository layout
app/ expo-router routes (screens)
src/ models, services, hooks, UI components
assets/ icons, splash, fonts
firebase/ Firestore + Storage rules and Cloud Functions
web/ Next.js marketing site + public session viewer (deployed on Vercel)
docs/ Canonical data model and architecture notes
Prerequisites
- Node 20+
npm i -g eas-cli (cloud builds — needed for iOS until you have a Mac)- A Firebase project (Auth, Firestore, Storage, Functions enabled)
- For local Android dev: Android Studio + an emulator or a device
- For iOS: a Mac with Xcode 16, or EAS Build (no Mac required)
First-time setup
npm install
cp .env.example .env # then fill in your Firebase web-app config
For the route map on Android you'll also need a Google Maps SDK for
Android API key (from Google Cloud Console → APIs → Credentials). Add it
to .env as EXPO_PUBLIC_GOOGLE_MAPS_ANDROID_KEY. iOS uses Apple Maps and
doesn't need any key.
Most things you can run today on Android from Linux. Background location,
Health Connect, and Sign in with Apple need a development
build (not Expo Go):
eas build --profile development --platform android
# install the resulting .apk on your device, then:
npx expo start --dev-client
When the Mac arrives, the same eas build --profile development --platform ios
gets you the iOS dev build. No project config changes required.
Watch path
The Apple Watch app lives in targets/watch/ (SwiftUI, standalone GPS +
heart rate) and is embedded into every iOS build automatically by
@bacons/apple-targets — see targets/watch/README.md for the one-time
EAS credentials setup. Finished watch sessions transfer to the phone via
WatchConnectivity and sync through the normal pipeline. wear/ holds a
Wear OS (Kotlin) skeleton that is not yet buildable or shipped. The phone
remains the source of truth. See docs/architecture.md.
Roadmap
- Phase 1 — Phone vertical slice: record, save, sync, export GPX, write to Health.
- Phase 2 — Companion watch apps (Apple Watch + Wear OS).
- Phase 3 — Audio "hut" detection for side switches (custom TF Lite module).
- Phase 4 — Weather capture, social share card, third-party uploaders.
- Phase 5 — Standalone watch apps (record without the phone).
