For iOS Devices, the inbuilt Game Center lets you play and share games with your friends, track your progress using leaderboards, and much more.

You can synchronize your farm across multiple iOS devices using your Game Center account.

If you have not set up a Game Center account, you can do this in your device settings.

Once you have signed in, you can set up your Game Center account. The farm on this device will be connected to this Game Center Account. To play the same Farm on your other iOS devices, you need to sign in with the same Game Center account on those devices.

You can change the account you are signed in to by going to the settings on your iOS device and then selecting Game Center.

Tap ‘Sign Out’.

After you sign out, Game Center will be off. Turn it on again to sign in with a different Apple ID.

If you want to play with a different farm, you can create a new Game Center account and start to play a new farm. If you link 2 Game Center accounts to 2 different farms, you can play with 2 different farms on 1 iOS device.

For detailed information about using Game Center on iOS and its features, see Apple's Manuals. Game Center may not be available in all countries or regions, and the available games may vary by country or region.