I want to use the leader board in game center.

halley - it would help if you put which tier you are using in your requests for help.

So [Tier 2] how can I add GameCenter into my game?

or

How can I add GameCenter to my Tier 2 code?

Something like that if you are using Tier 2, etc.

If you are using Tier 2, I can suggest visiting the Apple dev site, it has walkthroughs on adding GameCenter to your XCode.

If you are using Tier 1, then you can't right now, but maybe it will be added in the future.

I am using Tier 2. I will search on the apple website. Thank you.