If you don't want that much help, the optional smart notes feature automatically deletes values from notes you have entered manually when they are no longer valid.
The optional auto-notes feature enters all of the notes into the puzzle for you and keeps them updated as you solve.
The optional error checker tells you when you have entered an incorrect or illogical value, allowing you to catch errors early and preventing needless frustration.
Five difficulty levels, from easy to insane, ensure that you will be able to find a puzzle that matches your skill level.
Take a journey to feudal Japan with Sudoku Free! With beautiful graphics and killer features, Sudoku Free! is the best Sudoku app available for iOS.
Two separate keypads, one for entries and one for notes, allow you to enter values quickly and easily.
No more tedious switching between entry mode and note mode to complete your puzzle.
With 3,000 total puzzles, you won't run out of puzzles any time soon.