WaterFast is the intermittent fasting timer built Watch-first: start, monitor and end your fast from your wrist — your iPhone always shows the exact same timer. Fasting zones, hydration and streaks. Nothing else.
No accounts, no setup, no fluff.
Pick your plan (16:8 free forever) and start the fast from iPhone or Watch.
Follow your progress through science-based fasting zones — from fat burning to autophagy.
End your fast, keep your streak alive and watch the calendar fill up.
Everything a fasting timer needs — and the Watch app the competition never got right.
Start and stop fasts from the Watch, even with your iPhone in your pocket. One shared timer, zero drift.
Know what's happening in your body: digestion, fat burning, ketosis, autophagy — hour by hour.
Log a glass of water with one tap on your wrist, with haptic confirmation. Synced to Apple Health.
Don't break the chain: a calendar of completed fasts, current and best streaks.
16:8, 18:6, 20:4, OMAD, 5:2 or fully custom hours (PRO).
No ads, no tracking, no account. Your data stays on your device and in Apple Health.
Zero charges $69.99/year for a fasting timer. WaterFast charges $9.99. Same core features. You decide.
Güije Studios has no servers and no databases. WaterFast stores your fasts and hydration only on your iPhone and, if you allow it, in Apple Health (HealthKit). No ads, no tracking, no account.