Sudoku Pro is the only Sudoku program that you'll ever need. It comes with a complete set of features including infinite puzzles, printable sudoku and boards of multiple sizes and difficulties.

1. Millions of generated puzzles - Never run out of puzzles to play.
SuDoku Pro generates the puzzles on the fly. This means that there are literally millions of puzzles that can be generated. You'll always have a new puzzle to play.

2. Custom Sizes - Simple or hard puzzles to suit your moode.
You can choose from one of four sizes: 4x4, 9x9, 16x16 or 25x25. You can choose how complex you want the puzzles to be.

3. Custom Difficulties - Play at a level that's comfortable for you.
You can choose from different difficulties, making each puzzle as easy or as hard as you want.

4. Pencil Marks - The advantages of a pencil without the mess.
By just holding down the shift key (or clicking the Pencil Marks Mode button) you can enter a pencil mark, which is a smaller, lighter number to remind you of the options for a given square. You can easily remove these later without any of the mess and effort required with the paper games.

5. Helpers, Hints and Cheats - Never get stuck or frustrated.
SuDoku Pro gives you as much, or as little help as you want. Everything from a simple output showing what numbers are left in the column, row and box for the current square, all the way through to having the software actually make the next move for you. You will never be stuck with an unsolved puzzle again. Learn how to play better by seeing what move the computer would make next.

6. Undo and Redo - It's easy to fix a mistake.
SuDoku Pro remembers every move you make, and the order you made them in. The Undo feature allows you to undo your previous moves, all the way back to your first move. This makes doing trial-and-error solving in the difficult games especially easy. The Redo function does the opposite of the Undo, just in case you Undo too many moves.

7. Save and Load - Stop at anytime and continue at anytime.
SuDoku Pro automatically saves your place in the current game, so if you close the game for any reason, the next time you open it up it will be precisely where you were the last time. It even restores your game timer. You can save puzzles for later, and they save away into a plain text file which you can email, backup, or even post to a forum. At any stage, you (or anyone with SuDoku Pro) can open that saved game and resume playing.

8. Timer - Time yourself, compete with your friends and family.
As soon as you begin a game the clock is ticking, you can pause the game and the puzzle is hidden from view, then when you unpause it the clock begins again and you can resume solving the puzzle. Compete with your friends and family.

9. Print Puzzle - Print out any puzzle and play it anywhere.
You can print in a variety of ways. You can print your current puzzle either in its original state, or with your moves so far. You can also set SuDoku Pro up to print out any number of randomly generated puzzles for you. So you can print out a bunch of puzzles for your friends and family, or just for yourself.

10. Email Puzzle - Email a puzzle to your friends or a family member.
You can email your puzzle either in its original state, or showing your moves so far. This is great for sharing difficult puzzles with your friends, or challenging them to complete a puzzle in less time than you.

The license of this software is Free Trial Software, the price is $12.90, you can free download and get a free trial.