Swamp Numbers is a free program that helps you solve Sudoku puzzles. You can either work puzzles that it generates or puzzles that you enter from a book or newspaper. Swamp Numbers supports 6x6, 8x8, and 9x9 puzzles.
If you need helping solving the puzzles, simply enable Swamp Numbers hint capabilities. You can either have Swamp Numbers simply identify errors you make or ask for hints when you are stuck. For difficult puzzles, Swamp Numbers allows you to enter candidate values in each cell to help you apply more advanced solution techniques.
When working puzzles generated by Swamp Numbers, ten levels are available ranging from simple puzzles to those that will challenge experienced solvers. Swamp Numbers places no limit on the number of puzzles you generate.
Swamp Numbers supports number entry through the traditional "pick a square pick a number" method as well as "one flick entry" where flicking from a square in a specific direction selects that square and a number to enter in one gesture.
The integrated help explains the various features and also provides tips on solving puzzles. A "Fill Easy Squares" option in puzzle generation allows the generation of puzzles having everything filled in up to the point where an advanced rule is required. This can be used to train on specific solution strategies.