Privacy
Last updated 21 October 2026
OnCenter is built on a simple rule: your calculations belong to you, stay on your devices, and aren't shared with anyone, including me. This page says exactly what that means.
What OnCenter keeps on your device
- Saved tapes (Pro): each job's name, its calculation lines, any labels you gave them, their results and dates. They're stored with Apple's SwiftData.
- Preferences: your theme, and with Pro your default precision and unit.
- The widget's answer: your last answer and the two tape lines above it, kept where only OnCenter and its own widget can read them, so the widget can show them.
The tape you're working on and haven't saved is held in memory only and is gone when the app closes.
iCloud sync
If you're signed in to iCloud, OnCenter syncs your saved tapes across your own Apple devices through your private iCloud database. Apple encrypts it in transit and at rest, and neither I nor anyone else can read it. Apple's privacy policy covers this sync: apple.com/legal/privacy.
You can turn iCloud off for OnCenter at any time in iOS Settings → your name → iCloud.
Export
A tape leaves the app only when you share it, as text or CSV, through the iOS share sheet, to wherever you choose.
What OnCenter does not do
- No accounts, logins or sign-ups
- No analytics, advertising or tracking of any kind
- No crash-reporting services (Apple's own reports follow your iOS settings)
- No server of mine that the app talks to
- No camera, photos, location, contacts or notifications
- No selling or sharing of data, because there is none to sell or share
In-app purchase
OnCenter Pro is a one-time in-app purchase, handled entirely by Apple through the App Store. No payment details or personal information reach me. Pro is restored on any device signed in to the same Apple ID.
Calculations
OnCenter works out measurements exactly, but it's a calculator, not an inspector. Stair limits are general IRC defaults, not a check against your local building code. Measure twice, and follow the code that applies to your job.
Children
OnCenter is made for a general audience. It doesn't collect data from anyone, including children under 13.
Changes to this policy
If this policy changes, the date at the top will change with it, and real changes will be noted in the App Store release notes.
Contact
Questions about this policy? See the support page or email oncenter@charithp.com.