Noctium, developed by Obelisk Agency, does not create user accounts and does not store any personal data on our servers. All your Noctium data lives on your device, with one optional exception: backups you explicitly upload to your own Google Drive. Because we have nothing on our side, data deletion is something you perform directly from the app or your Google account.
1. Delete all Noctium data from the app
The in-app wipe is the fastest and most complete option. It runs entirely on your device.
- Open Noctium.
- Go to Settings → Privacy & Data.
- Tap Disconnect & wipe all data.
- Confirm twice. The app then closes automatically.
When you reopen Noctium, you will land on the initial onboarding screen as if the app were freshly installed.
2. What gets deleted
- Every saved server connection (Calibre-Web, Kavita, Audiobookshelf), including usernames, passwords, and API keys
- Your entire library: books, audiobooks, and files that Noctium downloaded or imported into its own storage
- Books you read in place from a folder on your device are removed from the library, but the original files stay in your folder and are never deleted
- Bookmarks, highlights, annotations, and vocabulary entries
- Reading progress, reading statistics, streaks, and reading goals
- Collections and favorites
- All app preferences (theme, font settings, playback speed, etc.)
- Onboarding state
- Cached cover images and downloaded content
- Your Noctium backup in Google Drive, when Google Drive is connected on that device (the app tells you afterwards whether it was deleted)
- Your Google Drive sign-in session (if you were signed in), along with the app's own cached Drive backup state
- Your Readwise access token (if you connected Readwise), and the app's record of which highlights it has sent
- Your Hardcover API token (if you connected Hardcover), and the app's record of which books it matched and which highlights it has sent
3. What stays, and how to delete it
Google Drive backup file. If you ever used the optional cloud backup feature, a backup ZIP lives in Noctium's private App Data folder on your Google Drive. The in-app wipe deletes it when Google Drive is connected on that device, and says whether it did. If it could not (no connection, or Drive was not connected on that device), remove it yourself:
— In Google Drive on the web (drive.google.com), open Settings → Manage apps, find Noctium, and choose Options → Delete hidden app data.
— Uninstalling Noctium from your phone does not delete it, and neither does signing out.
Highlights sent to Readwise. If you connected Readwise, highlights already sent there stay in your Readwise account; the wipe only disconnects this device. Delete them in Readwise at readwise.io.
Books and quotes sent to Hardcover. If you connected Hardcover, the reading statuses, progress and quotes already sent stay in your Hardcover account; the wipe only disconnects this device. Manage them at hardcover.app.
Third-party analytics and ad records. Aggregate analytics events, crash reports, and AdMob ad-targeting records held by Google (Firebase Analytics, Firebase Crashlytics, Google AdMob) are not stored by Obelisk Agency and are governed by Google's own retention policies. To clear these:
— Disable analytics in advance at Noctium Settings → Privacy & Data → Share anonymous analytics & crash reports.
— Delete Firebase-held data in your Google account's My Activity.
— Reset or opt out of the Android Advertising ID in your device's Settings → Google → Ads.
4. Retention periods
- On your device: 0 days after wipe. Data is deleted immediately and irrecoverably.
- Google Drive App Data backup: kept in your Drive until you delete it as described above.
- Firebase Analytics event data: retained by Google for up to 2 months (we have set data retention to the shortest supported window).
- Firebase Crashlytics crash reports: retained by Google for up to 90 days.
- AdMob / Advertising ID: Google's retention applies; see Google's Privacy Policy.
5. Can't open the app?
If Noctium is not installed or will not open, uninstalling the app still removes all local data. Uninstall from your device's settings or from the Google Play Store listing. For the Drive App Data backup, delete it from Google Drive as described above.
6. Help or questions
If you cannot complete the steps above, or if you believe personal data is being retained that should have been deleted, contact us at the address below and we will respond within 30 days.