Free Sudoku on your Pocket PC

Sudoku has turned into one of the most popular puzzles around, filling newspaper pages and puzzle books everywhere. It was only a matter of time before it took over handheld computers too, and the Pocket PC turns out to be an almost perfect Sudoku machine: a stylus to tap numbers, a screen that fits the grid comfortably and a device that is always in your pocket. This thread collects free Sudoku options for the platform and what players think of them.

How the puzzle works

Sudoku, also known as Number Place, is a logic puzzle. The grid is made of nine rows and nine columns, divided into nine smaller boxes. Some cells are already filled in. The goal is to complete the grid so that every row, every column and every box contains each digit from one to nine exactly once. No arithmetic is required: the digits could just as well be letters or symbols. Everything depends on deduction.

Free options for handhelds

Several free Sudoku programs are available for the Pocket PC. One that comes up often in discussion is SuDoku by Chris Baker, a freeware application with versions for Pocket PC as well as for Windows and Linux, so you can carry on puzzling on your desktop with the same tool. Other free games and online puzzle sites offer new grids regularly, and some even let you print puzzles to solve on paper.

What makes a good Sudoku app

• Puzzle generator: an endless supply of new grids instead of a small fixed set.
• Difficulty levels: from gentle warm-ups to fiendish grids that need advanced techniques.
• Pencil marks: the ability to note candidate numbers in a cell is essential for harder puzzles.
• Error checking: optional highlighting of conflicts, which you can switch off for a purer challenge.
• Save and resume: handheld sessions are short, so the game should remember where you stopped.
• Readable grid: clear digits and good contrast on a small screen.

Tips for beginners

Start with the rows, columns and boxes that are already mostly filled: the fewer empty cells, the easier the deduction. Scan each digit across the grid to find the only place it can go in a box. When you get stuck, write candidate numbers in the empty cells and look for cells with a single possible value. With practice, patterns such as pairs of candidates sharing two cells will jump out at you.

Share your favourites

Have you found a Sudoku game for your Pocket PC that you cannot put down? Post your recommendations, compare features and tell other members which version handles pencil marks and difficulty best. The more players contribute, the easier it will be for newcomers to pick the right puzzle for their device.