Simple Sprint Timer vs SprintTrac

I originally built this app for my wife, and wanted to share it in case anyone else finds it useful. It's still in very early beta — expect rough edges, and feel free to reach out with feedback. I've released the source code for free on GitHub in case anyone wants to tinker with it: https://github.com/jasonnmark/SprintTimer

Train at full speed. Never look down. SprintTrac turns your iPhone and Apple Watch into a precision sprint coach. Set your distance, sprint count, and rest time — then just run. The instant you hit your target distance, your wrist buzzes. No glancing at screens, no guessing where the line is. Just pure, focused speed work. Accurate where it matters GPS and stride tracking work together — fused in real time — to nail your distance on any surface: track, turf, grass, or pavement. Everything you need mid-sprint Live distance, split time, heart rate, and speed on your wrist. Audio cues count you down — Ready, Set, GO — and a rest timer tells you exactly when to line up again. No Watch? No problem. iPhone-only mode runs the full workout with phone haptics and GPS — perfect if your Watch is on the charger. Go further with SprintTrac Pro (one-time purchase — no subscription, ever) Stride calibration — run one measured distance and SprintTrac dials in to your exact running form for maximum accuracy Workout history — every lap, every split, every session, saved automatically Pace & performance analytics — speed trends, personal records, and rep-to-rep conditioning analysis Apple Health sync — workouts saved with GPS route maps CSV export — your data, anywhere you want it Built for sprinters, field athletes, and coaches who want precision training — not another app to fiddle with.