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Sync and offline use

Updated on August 5, 2026

With a single NoxDragon account, all your Deck Packs and cards are available on every device where you sign into EON.

How sync works

Every time you create, edit, or delete a card, EON saves the change locally right away and sends it to the server as soon as there is a connection. You don't need to do anything manually — sync is continuous and automatic.

Sync status indicators

The sync indicator at the bottom of the interface always shows where the process stands:

  • Synced — everything is up to date on the server.
  • Syncing — changes are being uploaded or downloaded.
  • Pending changes — there are local changes waiting to be sent.
  • Waiting for sync — the app is queued to sync.
  • Sync Failed — something prevented a change from being saved to the server.

If you see the error status, check your connection and wait a few seconds. Most errors resolve on their own when connectivity is restored.

Working offline

You can use EON without internet. Your cards, decks, and recent review history are stored locally on your device. You can study normally and the results will upload to the server the next time you have a connection.

If a card image had not been downloaded before you went offline, it may not display until you reconnect.

How conflicts are resolved

If you make changes to the same item on two different devices without syncing in between, EON detects the conflict and applies an automatic resolution. In most cases this is transparent. If a conflict requires attention, the app will let you know.

Force sync

Force sync is the last resort when a deck or Deck Pack you deleted or changed is not updating on a specific device. To use it, open Review Preferences and scroll to the Force sync option.

When you confirm with Yes, force sync, the app wipes all local data on that device and re-downloads everything from the server from scratch. You will not lose any data that is on the server. You stay signed in.

Use force sync only when other methods have not worked. It is not needed in normal use.

Frequently asked questions

Is my data safe if the app closes unexpectedly? Yes. EON saves changes locally before sending them to the server, so even if the app closes without warning, the changes stay on the device and will upload next time.

How many devices can I use at once? You can use your account on as many devices as you like. All of them sync with the same server.

What happens if two devices edit the same card at the same time? EON applies automatic conflict resolution. If the result is not what you expected, you can edit the card manually.

Does force sync sign me out? No. It only rebuilds the local copy; your session stays active.

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