The screen, the proof, and the pitch

The React screen never learned about platforms

Both native backends emit the same { meters, confidence } event, so the screen is one file that runs unchanged on iOS and Android. It renders the camera full-bleed, overlays a center crosshair, and shows the live distance. The only JS-side logic worth adding is throttling — the native side fires 30–60×/sec, more than a calm UI needs.