NistisThat's the policy. The rest of this page just spells out what "nothing" means.
What stays on your device
Everything you put into Nistis — your fasts, weight, water, notes, settings, streaks. It's stored locally on your phone and your watch: your iPhone and Apple Watch, or your Android phone and Wear OS watch. There is no Nistis server, no account, no sign-in, and no way for us to see your data.
Syncing between your devices
On iPhone, optionally turn on iCloud sync and your data is mirrored to your private iCloud database, managed by Apple and readable only by your devices. We can't access it. Turn it off any time; the app works fully offline.
On Android, there is no live cloud sync. Your phone and your Wear OS watch talk to each other directly, and nothing in that exchange reaches us. If you back your phone up to your Google account, your Nistis history is included in that backup — stored by Google under your account, encrypted with your screen lock, and restored when you set up a new phone. We can't read it; delete it any time by deleting the device backup in Google One.
Apple Health (optional, Pro, iPhone only)
With your permission, Nistis reads and writes weight and water entries only — never anything else, and never your fasts. Revoke access in the Health app any time; your local data stays.
Health Connect (optional, Pro, Android only)
Same scope, same rules. With your permission, Nistis reads your weight and hydration entries from Health Connect so entries from other apps and devices appear in your log, and writes back only the weight and water you type into Nistis yourself. It never writes your fasts (there is no fasting type, and inventing one would put a claim in your health record that this app isn't making), never reads anything else, and reads only while the app is open. Health Connect keeps its data on your phone; Nistis sends none of it anywhere. Turn any of it off in Health Connect at any time — everything already imported stays in Nistis.
Purchases
Payments are processed by the store you downloaded Nistis from. On iPhone, unlocking Pro across your devices uses RevenueCat, which processes an anonymous identifier and your receipt — no name, no email, nothing about your fasting. It's the only third-party service in the iOS app, and it exists solely so "Restore Purchases" works. On Android, purchases go through Google Play Billing, and unlocking Pro across your phone and watch uses the same RevenueCat service with the same anonymous identifier and receipt — nothing about you or your fasting. Google Play's billing component also sends Google a short report on whether it could connect and complete the purchase: your phone's model and software version and the result, nothing you entered. Google Play and RevenueCat are the only two places the Android app ever talks to.
What we don't do
- No analytics or tracking SDKs
- No ads, no ad identifiers
- No crash-reporting services
- No email collection, no newsletters
- No selling, sharing, or monetizing data — we never have it in the first place
This website
Everything above is about the app. This website (nistis.com) uses Google Analytics to count visits and see which pages people read — aggregate page views only, no ad personalization, and nothing that connects a visit to anything you do in the app. It's a static site with no accounts and no forms. If you'd rather not be counted, a content blocker will stop it and the site works exactly the same.
Your data is portable
Export everything as JSON or CSV from Settings whenever you like, on either platform. Deleting the app removes everything stored locally — and its iCloud data too, if you're on iPhone and had sync on. Your device (and your iCloud, if you use it) are the only places your data ever lives.
Questions
Email [email protected].
Last updated October 23, 2026. If this policy ever changes, the change will be listed here — but the first line isn't changing.