If Number of squares < 17 you will be playing tic tac toe. Winner is first to 3 in a row, yes, even if board is 3 x 4 or 4 x 4.

If Number of squares > 17 and < 64 you will be playing connect 4. Winner is first to 4 in a row.

If Number of squares = 64 you will be playing othello / reversi. Not all of the game logic was finished, so the app will not declare a winner. Also some illegal moves are not prevented, so please play nice :-).

If Number of squares > 64 the app will draw a gameboard, but it won't know what to do beyond that.