jsiSudoku

The Sudoku with everything. 9 Levels, cheat mode, illegal moves indicator, undo, redo, hints, marks, print to PDF, multiple skins, stay-on-top, transparent board option.

Free jsiSudoku is a fast & friendly Sudoku game with 9 levels. It has a built-in puzzle generator which works very fast to generate puzzles at several levels of difficulty. This means you always get a unique puzzle every time you play.

A special "Marks Mode" lets you enter multiple numbers in each cell, just like you do on paper, to store possible moves as you solve the puzzle.

A built-in Print to PDF feature lets you generate a printable version of any puzzle along with the answer key with a single click.

jsiSudoku makes it easy for those getting started with Sudoku: A special "Oops" indicator lets you know if your move breaks any Sudoku rules, a "Cheat-Mode" will help you if you get really stuck, and a Hint feature will keep you going

Multiple skins to match your mood.

Practically Undo / Redo makes play easier and lets you back-track without having to restart.