Logging into Facebook gives you access to many amazing features: free energy, competing against friends, and playing across devices, such as via your iPhone and your iPad.
It also enables you to securely save your progress in case your computer or mobile device crashes, or when you want to transfer your game from an old device to a new one.
It also enables you to securely save your progress in case your computer or mobile device crashes, or when you want to transfer your game from an old device to a new one.