You play Sudoku by filling in the empty boxes on the grid with numbers from 1 to 9, so that every row, every column and every 3x3 square does not contain repeating numbers. You can select a box and then tap a number to set it. The rule might seem easy at first, but mastering the quick thinking of this puzzle is not easy. You do have some helpers, though, like a notes mode that displays three possible numbers when turned on. You can also accept the hint or undo your moves. You can choose between five difficulty levels. Solve puzzles to earn points and see your score rise up the leaderboard. The harder the level, the more points you will earn. Now enjoy the game and become a Sudoku master!