Game Development Reference
Apple's servers and accessed either by your game or by the Game Center app that's in-
stalled on all devices running iOS 4.1 or newer.
Note The easiest way for a user to check whether a device supports Game
Center is to locate the Game Center app on the device. If it exists, the device is
ready for Game Center; otherwise, it's not. If the Game Center app isn't avail-
able, but the device is eligible for upgrading to iOS 4.1, Game Center support
will become available after upgrading the device's operating system via iTunes.
If you don't have access to a Game Center-enabled device, you can still pro-
gram and test Game Center features using the iPhone/iPad Simulator. With
the exception of matchmaking, all Game Center features can be tested in the
On the other side, the Game Kit API is what you use to program Game Center features.
Game Kit provides programmatic access to the data stored on the Game Center servers
and is able to show built-in leaderboards, achievements, and matchmaking screens. But
Game Kit also provides features besides Game Center—for example, peer-to-peer net-
working via Bluetooth and voice chat. These are the only two Game Kit features
already available on devices running iOS 3.0 or newer.
The final ingredient in this mix is iTunes Connect. You set up your game's leader-
boards and achievements through the iTunes Connect web site. But most importantly,
iTunes Connect lets you enable Game Center for your game in the first place. You'll
start with that step first, so you should do this before you've even created an Xcode
project for your game.
Your starting point for learning more about Game Center and the steps involved in cre-
ating a game that uses Game Center is at Apple's Getting Started with Game Center
Creating Your App in iTunes Connect
The very first step is to log in with your Apple ID on the iTunes Connect web site: ht-