iCloud Photos syncs one photo library across devices, while iCloud Backup stores eligible device and app data that is not already synced. A local-only app may keep its working data on one device, but you must check whether backups include it. Export provides a separate copy whose destination you control.
Sync, backup, and export solve different problems
| METHOD | MAIN JOB | DELETION EFFECT |
|---|---|---|
| Sync | Keep the current state consistent across devices. | A deletion usually propagates. |
| Backup | Restore eligible device or app state after loss or replacement. | Depends on retention, timing, and inclusion rules. |
| Export | Create a readable copy in a destination you choose. | The copy remains until removed from that destination. |
Using the words interchangeably creates false confidence. Start by identifying which system holds each copy.
iCloud Photos propagates library changes
iCloud Photos keeps the Photos library synchronized across devices using the same Apple Account. Edits appear elsewhere, and deleting a photo on one device deletes it on the others. Recently Deleted provides a 30-day recovery window.
When iCloud Photos is active, the synchronized library is not duplicated inside the daily iCloud Backup. Apple explains both the sync behavior and storage options in its iCloud Photos documentation.
iCloud Backup includes eligible app data
Apple says iCloud Backup can include app data that is not already synchronized through another iCloud service. Inclusion still depends on the app and the user’s backup settings. Some protected app files can be deliberately excluded.
- Check whether the app offers its own account or cloud backup.
- Check iCloud Backup settings for the device and app.
- Check whether the app explicitly excludes its protected files.
- Keep a verified export when restoration matters.
See Apple’s iCloud Backup guide for the platform-level rule. The iPhone photo storage map shows where Photos and app copies fit.
Calculator Lock has a local vault and external purchase processing
Calculator Lock stores encrypted vault content and sensitive vault metadata locally. The launch version has no Calculator Lock account, developer content server, cloud backup, or cross-device sync. Its current vault files are excluded from device backup, so deleting the app can permanently remove them.
Local vault storage does not mean the entire app avoids external services. Apple processes purchases, and RevenueCat receives anonymous purchase history and transaction status to validate the Premium entitlement and provide subscription functions. RevenueCat does not receive vault content.
Review the local photo vault model before relying on it for the only copy of a file.
Choose a copy plan before device loss or uninstall
- List every location that holds the important files.
- Mark which locations synchronize deletions.
- Mark which backup or export can be restored independently.
- Open sample files from the independent copy.
- Repeat the export when the protected collection changes materially.
Fewer copies can reduce exposure, but one device should not become the only untested copy. Use the photo vault export checklist before uninstalling or replacing the phone.