Play tic-tac-toe against the computer in 5 levels of difficulty. This app is called "Tiny Tic Tac Toe" because the original version of this app is really tiny. This is the free (ad-based) version of "Tiny Tic Tac Toe (Premium)": https://play.google.com/store/apps/details?id=com.goodtemperapps.tinytictactoe The free version needs more space on your device than the premium version but it's still small compared to other apps. You can find the source code of this app (without the advertisement part) at GitHub: https://github.com/MaxGyver83/TinyTicTacToe