Zone 2 training with haptic heart rate zone alerts — so you never have to stare at your watch. DaInterval Pro is the interval trainer for building your aerobic base: set your zones, start running, and let gentle vibrations tell you when to ease off or pick up. ZONE 2 WITHOUT WATCHING A short buzz when you drift high, a different buzz when you drift low. Eyes on the trail, mind at ease, heart rate exactly where it should be. This is effortless aerobic training — Wu Wei for your cardio. EVERYTHING IN DAINTERVAL, PLUS - Haptic alerts for heart rate zone drift — no screen-checking required - Detailed pre-workout readiness measurements - Detailed post-workout stats: time in zone, drift, interval-by-interval breakdown - Improved in-workout data screens - Custom heart rate ranges for true Zone 2 intervals, tempo work or recovery runs BUILT FOR THE LONG GAME Zone 2 is the highest-return training zone for people 40 and up: a stronger heart, better fat metabolism and joints that thank you. DaInterval Pro keeps you there without strain, spreadsheets or staring. Free to install; one-time unlock for Pro features. Pairs with FastFlow — the only fasting tracker with live Garmin sync — for the full Effortless Longevity toolkit. Website: fastflowapp.com Support: [email protected]

[July 22, 2026] - [Feature/fix] - [Device support added] DaInterval Pro has no reviews yet — if the haptic alerts changed your runs, you'd be the first to say so. Support: [email protected]