Advanced Sudoku App for iPhone and iPad

For an iPhone or iPad app that offers Sudoku puzzles from easy to advanced Sudoku try Big Bad Sudoku Book from By Bad Weasel, LLC.

This app provides a range of Sudoku difficulty levels from Easy, Medium and Hard to Expert and Insane. And these include difficult Sudoku puzzles that require the use of advanced Sudoku strategy techniques. This app can be bought from Apple's iTunes store.