Backup & Sync

Backup & Sync

Tsumihon keeps your library synchronized across all your devices in near real-time. Just sign in with your account and your collection stays in sync automatically — no setup required.

Cloud Sync

Real-time sync is the core of Tsumihon’s multi-device experience. When you add, edit, or delete a book on any device, the change is propagated to all your other devices automatically.

  • Near-instant propagation — changes typically arrive on other devices within ~10 seconds.
  • Conflict-free — the sync system handles concurrent edits gracefully, using timestamps to resolve conflicts.
  • Selective sync — metadata syncs automatically; large assets like downloaded pages are managed separately.

Tip: Cloud sync is enabled automatically when you sign in. There’s nothing extra to configure.

How Sync Works

The sync pipeline follows a push-notify-pull architecture:

  1. Device A makes a change — a book is added, edited, or deleted.
  2. The cloud stores the change — the updated record is written to the cloud database.
  3. Push notification sent to other devices — all other devices for the same user receive a notification.
  4. Other devices refresh — upon receiving the notification, each device pulls the latest data and updates its local cache.

This architecture ensures that devices stay in sync even when the app is in the background, as long as push notifications are enabled.

Background Sync

In addition to real-time push-based sync, Tsumihon runs a periodic background task to catch any changes that may have been missed (e.g., if the device was offline when a push was sent).

  • The background sync task runs approximately every 1 hour.
  • It is managed by the OS task scheduler and runs automatically.
  • Each run performs a full diff between the local database and the cloud, pulling any missing changes.

Automatic Backups

Tsumihon automatically backs up your library data to the cloud on a regular schedule. You don’t need to trigger backups manually — the app handles everything in the background.

Tip: Backups happen automatically as long as you’re signed in. No manual intervention needed.