Transferring the app is no problem, since your app account is stored in the e-mail account you used for purchase.
Important: you must use the same login data in the app on the new device.
You can check which app accounts are stored on which e-mail address here:
https://solutions.mycarly.com/users/request_accounts_info
If your app does not work, please restore your app account:
Android: https://carly.zendesk.com/hc/en-us/articles/360008675559-App-Restore-Unsuccessful
iOS: https://carly.zendesk.com/hc/en-us/articles/360010824360-App-Restore-Unsuccessful
If you still experience problems with your app, please contact our Support Team here.
We'll get back to you shortly. 😊