iPhone
Fastwell
The fasting app that teaches you why, not just when. Track fasts from 16:8 to extended protocols, learn what is happening in your body at every metabolic milestone, and build the knowledge to fast safely. Science first.
What It Does
Science-based fasting timer covering 16:8 through extended protocols, with live metabolic-zone tracking so you see what stage your body is in, not just an elapsed clock.
A guided phase-by-phase journey through fasting science — 50+ education modules on autophagy, ketosis, hormones, and refeeding, unlocked as you reach metabolic milestones.
An adaptive quiz engine with spaced-repetition-style review that tracks mastery across the core fasting-science topics for long-term retention.
Apple Health integration for weight, heart rate, sleep, and glucose trends; built-in safety check-ins and refeeding guidance for longer fasts; home-screen widgets and Live Activities for active fasts.
Plans
Free
$0
Fasting timer with metabolic-zone tracking, the guided science journey, education modules, quizzes, safety check-ins, and home-screen widgets. Enough to run real fasts and learn the science before deciding on premium.
Premium Monthly
$3.99 / month
Everything in Free plus extended fasting protocols (36h+), advanced education tiers, and the full analytics dashboard. Includes a 1-week free trial. Auto-renews monthly until cancelled.
Premium Yearly
$24.99 / year
The same premium feature set billed yearly. Includes a 1-week free trial. Auto-renews yearly until cancelled.
Lifetime
$49.99 one-time
All premium features forever with a single non-consumable purchase tied to your Apple ID. No subscription, no auto-renewal.
Fastwell is free to use. Premium is optional. Monthly and yearly plans are auto-renewable subscriptions with a 1-week free trial, billed through your Apple ID; the Lifetime option is a single non-consumable purchase. Manage or cancel anytime in your Apple ID subscription settings.
Privacy
Fastwell is local-first. Your fasting history, weight log, quiz progress, and journey state stay on your device. Fastwell does not require an account, does not use third-party analytics or advertising SDKs, and does not transmit your health or fasting data to any server. Apple Health data is read on-device with your permission and is never sold or shared.
Health Disclaimer
Fastwell is an informational and self-tracking tool. It is not a medical device and nothing in the app is medical advice. Fasting carries real medical risks. Consult a qualified healthcare professional before fasting — especially if you have a medical condition, take medication, are pregnant or breastfeeding, or have a history of an eating disorder. Fastwell is rated 17+. Full terms are in the app under Settings → Legal and at the links below.