ZenFast Tracker
A simple, private intermittent fasting timer for iOS and Android. Pick a plan, start your fast, and track your progress through each metabolic phase — with no account, no ads, and no data collection of any kind.
Coming soon to iOS and AndroidWhat ZenFast Does
Preset & Custom Fasting Plans
Popular presets like 16:8, 18:6, 20:4 (Warrior), and OMAD, plus extended 24/36/48/72-hour fasts. Build fully custom sequential or weekly schedules of your own.
Live Phase Tracking
A live countdown paired with plain-language education on each metabolic phase of your fast — from the initial digestive window through ketosis and autophagy.
Fully Private by Design
No sign-in, no cloud sync, no analytics, no ads. All fasting history and preferences stay on your device and nowhere else.
Light/Dark Theme, 5 Accent Colors
A clean Material Design interface with a light or dark theme and five accent color options.
Privacy
ZenFast collects, transmits, and has access to none of your personal information. There are no user accounts, no servers, and no third-party SDKs of any kind. All of your fasting history, plans, and preferences stay on your device. See the full Privacy Policy for details — it's the same on iOS and Android, since there's nothing platform-specific to disclose.
Frequently Asked Questions
Does ZenFast Tracker require an account?
No. ZenFast has no sign-in and no accounts of any kind. It opens straight into the fasting tracker.
Does ZenFast Tracker collect any data?
No. ZenFast collects, transmits, and has access to none of your personal information. All fasting history, plans, and preferences are stored only on your device and are never sent anywhere.
How much does ZenFast Tracker cost?
ZenFast Tracker is completely free, with no ads and no in-app purchases.
What fasting plans does ZenFast Tracker support?
Popular presets like 16:8, 18:6, 20:4 (Warrior), OMAD, and extended 24/36/48/72-hour fasts, plus fully custom sequential or weekly fasting schedules.