App Id. Just sign in with the same apple id everywhere. Using a 128 bit globally unique identifier guid that identifies the appid key.
Your apple id is the account you use for all apple services. Using a 128 bit globally unique identifier guid that identifies the appid key. All characters must be alphanumeric or an underscore.
This mapping is used during activation.
How to sign in. Keep your settings and apple services up to date on all of your devices. App id enables you to see the applications on your network and learn how they work their behavioral characteristics and their relative risk. All characters must be alphanumeric or an underscore.