If you already connected your account, the data is automatically saved to that account.
This means that even if you delete the game or change the mobile device, you will be able to continue with your save data.

If you are playing as a guest, the data will be saved on our server, but changing your device or any kind of unexpected event may cause complete data loss that is unretrievable.
Therefore, we strongly recommend that you link your account to prevent any chance of losing your saved data.