Apple ID synchronization is the same way of saving your progress, like connection via Facebook.
It is a paw-some feature that guarantees your progress safety. It allows you to play on different devices and restore progress even if your device has been lost or broken.

Just click on the cogwheel, open "Settings," tap on "Sign in with Apple," and the progress will be synchronized with your Apple ID profile.
And if you want to play the same game on different devices, you should just make the same Apple ID connections on both of them. In this case, your game progress can be synchronized correctly.

We accept your choice not to use Apple ID/Facebook, but this is the only way of saving and transferring game progress/ coins/ gems to another device.