Back to apps
Health & FitnessComing soon
LockIN
Run smarter. Stay locked in.
LockIN is a Zone 2–first running coach. It calibrates a personal easy-effort heart-rate band, then keeps you inside it while you run — a live band chart on your wrist, gentle haptics, and a voice that says 'ease up' before you drift. An adaptive 80/20 plan builds toward your goal (5K to marathon, or just a solid base), and every run is scored by minutes in zone, not pace. Music comes along too: Apple Music with coaching cues ducked over your mix, and on-device AI playlists matched to your effort.
Drafts playlists with on-device Apple Intelligence — nothing is sent to AI servers. How we handle AI & your data.
Get notified →7:04
Easy run · Zone 2
142bpm
✓ Locked in
24 min in zone
Features
Live heart-rate coaching on 'The Line' — your personal Zone 2 band
Voice cues and directional haptics when you drift high or low
Personalized zone calibration, with three methods and manual override
Adaptive 80/20 training plans, from 5K to marathon
A full Apple Watch app that mirrors live to your iPhone
Runs scored by minutes in zone — not pace
Apple Music with coaching-cue ducking and on-device AI mixes