Wish to transfer or play the same game on multiple devices?
If you are using the same OS type, there's nothing to stop you!
But if you wish to play the same game on different OS types such as Android to iOS. Start by connecting your game to Facebook with Device A:
1. Go to in-game [Settings] > [Info]
2. Connect Facebook account by clicking [Facebook Login]
3. Log out from the game
4. Make sure you are NOT sharing an account with somebody else
To play with Device B, first download the game, and then:
1. Launch the game
2. Log in with your Facebook account
And you are playing the same game on multiple devices!