Fast: Intermittent Fast Timer

Track 16:8 fasting with an AI coach that adjusts to your hunger, sleep, and energy — not just a timer. 4-state phase ring. No LLM, no server.

Track 16:8 fasting with an AI coach that actually adjusts to your hunger, sleep, and energy — not just a timer.

4-state color coding: eating, fasting, autophagy, ketosis. Free basic 16:8. Pro unlocks OMAD / 18:6 / 20:4 / 5:2 + the AI coach that adapts daily.

THE AI COACH The "AI" is not an LLM call. It's a deterministic on-device engine that reads your sleep, HRV, weight trend, and activity from Apple Health, picks the right context from tens of billions of possible coach lines, and quietly suggests a gentler window after a poor night or a small push when recovery is strong. There is no server. Your fasting data never leaves your phone.

WHAT'S NEW IN v1.0.1 • Redesigned "precision watch" dark theme — full-bleed circular timer with 4 phase colors • Streak ribbon and phase chip pinned to the top of Today • Faster monospace countdown, sharper typography • New app icon — dark dial + amber hour ticks • Refreshed onboarding copy + paywall positioning

WHAT'S IN • All five protocols: 16:8 (free), 18:6, 20:4, OMAD, and 5:2 • On-device coach reading sleep, HRV, body mass, and active energy from Apple Health • Phase tracking: Clean Slate → Fat Burn → Autophagy → Ketosis, with gentle local notifications when you cross each one • Break-fast guidance — one hour before your window opens, a short card calibrated to your goal • Weekly adherence + weight-trend report • Water + electrolyte log

WHAT WE PROMISE TO SKIP • No streak-shaming notifications • No "you broke your fast" guilt pings • No before/after body photos in marketing or in-app • No supplement / electrolyte-powder affiliate links • No social comparison ("your friends fasted longer") • No selling, sharing, or trading your data — there is literally no server to sell it from

PRO (LIFETIME) $99 one-time. Unlocks all five protocols and the daily HealthKit-driven adaptation. The free tier is the real 16:8 timer with the coach line; you can use Fast forever without paying.

PRIVACY The coach engine ships entirely on your device. The free tier needs no login, no email, no analytics. HealthKit reads happen in-process and are never written to disk verbatim — only the bucket category is used. Anonymous receipts validate Pro. That's it.

NOT MEDICAL ADVICE Fast is a wellness companion. If you have a health condition, are pregnant or nursing, are managing diabetes or an eating disorder, or take medication that interacts with fasting, talk to a clinician before changing your eating pattern.