Sudoku Free

If you are tired of doing Sudoku puzzles with a medium or hard difficulty level and you no longer find the classic game to be so intellectually challenging, put yourself to the test using Sudoku Free and complete extremely difficult puzzles.

In this game you will find different game levels, including beginner, easy and normal. However, you also have to add modes including difficult, expert and legendary (the most diabolically difficult of all).

It has some features that you will be very thankful for, including the auto-save option as well as an option that reopens the same puzzle whenever you want to so that you don't have to start a new one every time you open the game.

It has a note-taking system that allows you to jot down the ideas that come to you as you are solving the puzzle and which might really come in handy at certain points.

It also has an undo function if you're not sure about the last few moves you've made, and it allows you to complete more than 6,000 different puzzles.

Sudoku Free is definitely one of the most comprehensive Sudoku apps that you will find.