You can create an account using an email address, a Facebook account or with your Apple ID to start playing.
If you want to register using your email address, select "Via email" and enter your email address. Finally, tap "Continue" and you can start playing.
If you want to create an account with your Facebook profile, select "Via Facebook". There you will be redirected to the application, where you must enter your account information. Then you can start playing.
Finally, you will be able to log in with your Apple ID. Once you do, the game will create an account that will be registered with your Apple ID information.