Run easy,
train smarter.
Heart rate zone training built around the Maffetone method. Real-time coaching on your wrist, training analytics on your phone.
Free · No account required 
Stay in the zone.
Everything you need for aerobic base building — nothing you don't.
Real-Time Zone Coaching
Your Apple Watch shows your current HR zone live — with haptic and audio cues when you drift out of your target.
MAF 180 Built In
Enter your age, get your zones. The Maffetone method removes the guesswork from aerobic base building.
Training Analytics
Cardiac drift, HR recovery, zone distribution, and weekly trends — see your aerobic fitness improve over time.
iPhone + Apple Watch
Start runs from your wrist. Review history, stats, and settings on your phone. Everything syncs automatically.
Live Activities
Track your zone from the lock screen and Dynamic Island without raising your wrist or opening the app.
Completely Private
No accounts, no tracking, no analytics. Your data stays on your device and syncs only to your own iCloud.
See it in action.
Home 
Run Detail 
Insights 
Run History 
Settings 
Active Workout 
HR Gauge 
Zone Distribution Start running easier.
Free on the App Store. No account required.
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