Periodly is an offline-first school timetable app for Android. Everything you create — teachers, classes, subjects, timetables — is stored on your device; we have no servers and never receive it. (Android's own device backup, if switched on, may still copy it to your own Google Drive — see Section 1.) We do not analyse your usage, and we do not share anything with third parties for advertising.
Two kinds of data pass through the app:
sub claim). This is the only way Periodly knows whose device this is.
Both kinds are stored in a local SQLite database on your phone. Periodly has no servers to upload them to, so we never receive this data. If you have Android Backup switched on, Android itself may still include Periodly's local database and any local snapshot files in your own Google Drive device backup, encrypted with your device credentials. That copy belongs to you, not to us — we never see it. You can exclude Periodly or disable backup in your device's Android settings.
When you sign in with Google, Periodly saves one small marker in Android's Block Store
(part of Google Play services): your Google account's stable identifier (the
sub claim) and nothing else — no name, no email, no school data, no
timetables.
Block Store rides Android's backup and device-to-device transfer infrastructure, so this marker can move to a new phone when you set it up from your old one, and it survives an uninstall/reinstall. When your device runs Android 9 or later and has a screen lock set, the marker is end-to-end encrypted while it is backed up to the cloud; otherwise it stays local to the device only. This marker is separate from, and much smaller than, any full app-data backup Android may make of your local database (see Section 1).
Its only purpose is to let Periodly ask Google to silently restore your sign-in when the app starts on a device where it recognises the marker — no taps required. Google Play requires apps with sign-in to support this kind of restoration on new devices (see Google's technical quality requirements).
When you sign out or use Delete my account, Periodly deletes the marker — and if it cannot (for example, Google Play services is briefly unavailable), the app tells you so and explains what to do. You can also revoke Periodly's access at any time from Google Account → Security → Third-party apps & services (myaccount.google.com/permissions), which disables silent restore on every device. Your timetable and school data never travels with this marker.
The app needs an internet connection only for two narrow purposes:
All other features work fully offline.
Periodly is intended for school staff and administrators. It is not directed at children under 13, and we do not knowingly collect data from them.
Sign-In traffic to Google uses HTTPS. Local data on your device is protected by Android's standard app sandbox — it is not encrypted at rest by Periodly itself. We recommend enabling a screen lock on the device.
If we make material changes, we will update the effective date above and announce the change in the app's release notes on Google Play. Continued use of the app after the effective date constitutes acceptance.
Questions, requests, or complaints: appzubair@gmail.com.