ThreeTGame

Put away your pencil and paper - now you can play Tic Tac Toe on your iPhone for free.
Tic Tac Toe Free supports one player and two player gameplay, so you can play against another human or against your iPhone.
The AI for one player mode includes three difficulty levels, so you can play against a computer player that matches your skill level. A move randomization engine ensures that your iPhone won't keep making the same moves over and over again.