This is not a sudoku game app, but a sudoku calculator (a sudoku solver or sudoku resolver) for figuring out a solution of an existing sudoku puzzle on you hand. You may also use it as a tool assistant to advise you an answer to an individual cell(s) without showing all the numbers.Its a free and clean app without advertisement. Click ? in the app to get dynamic help about how it works.This app is refactored and further developed based on a solution by CRISTIAN CANEA.