Calvin is a calorie tracker that keeps barcode scanning and food search free. If something is not working, or you want to ask for a feature, email me and a person will read it.
Email support@calvinhealth.com. Please say which iPhone and iOS version you are on, and what you were doing when it went wrong. If it is about a specific day's log, the date helps.
On your phone. Calvin has no accounts and no sign-in, and your food log is never uploaded. That also means it is not backed up to Calvin. Use Settings to export a CSV if you want your own copy, and keep iCloud device backup on if you want the app's data to survive a new phone.
Deleting the app deletes its data, and there is no server copy to restore from. Restoring the device from an iCloud or Finder backup made before the deletion is the only route.
Free: manual logging with full macros, barcode scanning, food database search, recents and usuals, copy yesterday, recipes, weight tracking and trends, Apple Health sync, the widget, Siri and Shortcuts, CSV export, and an on-device photo estimate.
Calvin Plus: the AI meal photo scan that reads a whole plate into separate foods, and deeper insights.
Subscriptions are handled by Apple, not by Calvin. On your iPhone open Settings, tap your name, then Subscriptions, and cancel there. You keep access until the period you have paid for ends. Refunds are handled by Apple at reportaproblem.apple.com.
Open Settings inside Calvin and tap Restore Purchases. If it still will not unlock, check that the Apple Account signed in on the device is the one that bought the subscription, then email me.
Barcode and search results come from public food databases, and packaged products sometimes carry per-100g figures where you expected per-serving, or an out-of-date label. Every scan has an editable confirm step before anything is logged, so you can correct it there, and the corrected version is what Calvin remembers next time.
If you have logged weigh-ins for about three weeks, Calvin works out your real maintenance calories from your weight trend against what you logged, rather than trusting a formula. That number moves as the trend moves. You can see and set it in Settings.
Only the optional Google Health, Fitbit, Whoop, and Hevy connections store anything on Calvin's server. Disconnecting in Settings erases it. Everything else is on your phone. See the privacy policy for the detail.
The full policy is at privacy.html.