Launch Monitor App

Android-first golf training app for FlightScope Mevo+. It connects directly to the device over TCP, captures shot data in real time, stores everything locally in SQLite, and adds training-focused analysis on top: target ranges, session stats, dispersion, history, and trend charts.

The project is currently at the end of Phase 2 and preparing for Phase 3.

Product Scope

This app is built for structured range practice, not generic launch monitor viewing.

Core user flow today:

1. Sign in with email/password.
2. Create and manage clubs in Equipment.
3. Connect to a Mevo+.
4. Start a session and assign an active club.
5. Capture shots live and save them locally.
6. Evaluate shots against per-club target ranges.
7. Review session stats, dispersion, history, and trends.
8. Optionally sync local data to Supabase when online.

The current product focus comes from docs/user-journey-v1.md. The expansion path for video, cloud workflows, and advanced coaching features is described in docs/user-journey-v2.md and docs/user-journey-v3.md.

Current Status

Implemented

• Mevo+ direct connection over TCP (port 5100)
• Live shot capture and structured dashboard
• SQLite offline-first storage for clubs, sessions, margins, and shots
• Supabase Auth with persisted session
• Equipment management
• Per-club target ranges
• Session statistics
• Shot dispersion view
• Session history
• Trend charts
• Cross-metric trend overview
• Manual SQLite to Supabase sync from Settings

In Progress / Next

• Phase 3 video integration
  • video recording linked to shot events
  • shot detail video player
  • annotations
  • local clip storage and optional Supabase Storage upload
• Phase 4 follow-up work
  • CSV export
  • cloud download / multi-device sync
• Phase 5+ longer-term direction
  • AI-assisted swing analysis
  • richer coaching and training workflows

Hardware Validation Still Open

• verify protocol byte offsets on the real device, especially FIL fields
• define the shot-event timing offset as a constant
• verify the camera stream on http://<mevo-ip>:8080
• confirm remaining protocol details with FlightScope support

Tech Stack

• Expo SDK 54
• Expo Router
• TypeScript
• React Native
• expo-sqlite
• Supabase Auth + sync
• victory-native for charts
• @shopify/react-native-skia for graphics
• expo-video for upcoming video workflows
• @bri-b-dev/gspro-connect-mevoplus for Mevo+ communication

Architecture

App Structure

app/(auth)/             Login and registration
app/(app)/              Authenticated app screens
app/(app)/session/      Live training/session flows
app/(app)/history/      Session history, analysis, trends
app/(app)/equipment/    Club setup and management
app/(app)/settings/     Sync and account settings
components/             Reusable UI and chart components
lib/db/                 SQLite setup and database access
lib/hooks/              App state, auth, Mevo, and data hooks
lib/supabase/           Supabase client and sync logic
lib/utils/              Unit and domain helpers
supabase/migrations/    Cloud schema and RLS history

Data Model

Local-first storage is centered around:

• users
• clubs
• launch_monitors
• sessions
• shots
• margins

The shots table is designed to support later video workflows through video_path and video_url.

Mevo+ Integration

• direct TCP connection on 5100
• flow: connect() -> configure() -> arm() -> receive shots
• shot events arrive shortly after impact
• camera preview stream is expected on HTTP 8080 and is not fully validated yet

Important shot fields include:

• ball data: ballSpeedMph, verticalLaunchAngle, horizontalLaunchAngle, totalSpin, spinAxis, carryDistanceYards
• club data when available: clubSpeedMph, angleOfAttack, clubPath, faceToTarget, dynamicLoft, spinLoft
• face impact data when available: faceImpactX, faceImpactY

If isEstimatedSpin === true, spin should be treated as unreliable.

Offline-First Behavior

• Shot capture and analysis work against local SQLite storage.
• Sessions and shots survive app restarts.
• Cloud sync is manual from Settings.
• Supabase is additive, not required for the training loop once the user is authenticated.

Setup

Requirements

• Node.js and npm
• Expo native development environment
• Android device or emulator for app builds
• FlightScope Mevo+ on the same network for real hardware testing
• Supabase project for auth and sync

Note: direct Mevo+ TCP communication is native-only. Browser/web builds cannot connect to the device.

Environment Variables

Create a local .env file with:

EXPO_PUBLIC_SUPABASE_URL=...
EXPO_PUBLIC_SUPABASE_KEY=...

Optional:

EXPO_PUBLIC_MOCK_MEVO=true

EXPO_PUBLIC_MOCK_MEVO=true enables a local mock shot flow for UI and data testing without real hardware.

Install

npm install

Run

npm run android

Mock mode:

npm run android:mock

Other useful scripts:

npm run start
npm run start:mock
npm run lint

Roadmap

v1

Stable training foundation:

• auth
• equipment
• Mevo+ connection
• shot capture
• local persistence
• target ranges
• session analysis
• dispersion
• history
• trends

v2

Measurement plus documentation:

• shot-linked video
• video playback and comparison
• annotations
• local/cloud video storage
• broader sync/export workflows

v3

Interpretation and coaching:

• AI-assisted swing analysis
• guided training insights
• richer long-term progress workflows

Detailed status and planning live in:

• docs/roadmap.html
• docs/user-journey-v1.md
• docs/user-journey-v2.md
• docs/user-journey-v3.md

Conventions

• TypeScript strict
• no any
• functional React components
• explicit props interfaces
• database access in lib/db/
• transactional writes for related entities
• internal units stay in mph, yards, and degrees
• field names follow ShotData exactly

Limitations

• Android-first product direction
• direct device connection requires a native build
• no simulator-based Mevo workflow
• video feature set is only partially prepared at schema/dependency level
• some hardware protocol details still need validation on a real device