To use the Game Center features of our apps you will need to be logged into a Game Center account. For devices running iOS 4 through 6, this can be done through the Game Center app on your device. When you open the Game Center app, you will be prompted to login using your Apple ID. Once you are logged in to Game Center, all of our apps that use Game Center will automatically detect it. For iOS 7+ users, logging into Game Center is done from the main Settings app on your device under Game Center. After logging into your account, when you open Game Center connected apps you should see a Game Center Welcome Back, (YourUserName) banner from the top of the screen to let you know that your Game Center account is connected.