A free program for Android, by 99 Up Games.

Puzzle IO Binairo Sudoku is a logic puzzle game with one of the best user interfaces of any game in the market. The free version of Puzzle IO is designed with beautiful graphics, animations, and a very easy and intuitive interface. The user can select the difficulty level of the game. 

The gameplay of Puzzle IO is very simple and fun. You only need to tap the boxes to place the numbers. The difficulty of the game increases with each level. Each level contains a grid of 10 by 10 boxes. Each row and each column must contain the same number of boxes. Three boxes in a row or three boxes in a column are not allowed. 

If you get stuck, you can ask for help from the user. The user can choose from several options, like removing a box, removing a row, or removing a column. The user can also choose to skip the current box. If you get the right answer, you get points and if you get the wrong answer, you lose points.

Puzzle IO is a logic puzzle game, which means that you have to use logic and knowledge to solve the puzzles.