Your goal is to match all sides of every tile on the board. Click on the left side of a tile to rotate it 90 degrees counter-clockwise. Click on the right side to rotate it 90 degrees clockwise. Click near the center to rotate it 180 degrees. Make as few moves as possible on your way to solving each puzzle. 

There are four board sizes: XS, S, M, and L. If you're new, try starting with an XS board--that's a 2x2 grid--to get a feel for the game. S is 3x3, M is 4x4, and L is a massive 5x5 grid.

If you get stuck, click on the question mark icon on the bottom of the screen to review the rules. If the puzzle gets too difficult, click on the second icon on the bottom row to see the solution. You can check your stats by pressing the third icon in the row.