Scrutor contains several game-tree search implementations in Objective-C. These can be used to create computer players for a whole range of games including Chess, Checkers, Go, Reversi/Othello, Connect-4 and Tic-Tac-Toe to mention but a few.
More specifically, this library can be used in all two-player, zero-sum, perfect information games. The term two-player just means that there must be two opposing sides. Football is considered two-player, for example. A zero sum game is one where an advantage for one player is an equally large disadvantage for the other. Perfect information basically rules out any game that has an element of chance. This last rule disqualifies Yatzee, Poker and--most definitely--Jenga.
The framework aims to be easy to use: there's no need for prior experience with game-tree search or Artificial Intelligence. You don't actually have to learn anything about game-tree search in order to use this framework.