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Official Description

Play tic-tac-toe against the computer in 5 levels of difficulty. It's called "Tiny Tic Tac Toe" because it's really tiny. Other tic-tac-toe apps need more than 1000 times the space of this app.

You can find the source code of this app at GitHub:
https://github.com/MaxGyver83/TinyTicTacToe