Beginning iOS Game Center and Game Kit: For iPhone, iPad, and iPod touch

An Overview of Leaderboards in Game Center

A leaderboard, in the sense of Game Center, is an array of GKScore objects related to a specific leaderboard identifier, of which many can exist per app. Leaderboards can be retrieved and further filtered based on friend status and date submitted.

GKScore objects represent each entry on a specific leaderboard. A GKScore always has a player ID associated with it. When submitting a new GKScore to a leaderboard, the player ID is set automatically by the API and cannot be changed. There are also values for the date and rank that are automatically set and updated. You are required to set only the raw score value and leaderboard category to which the score belongs.

There are two ways to retrieve and display ...