Sudoku-Game app for iPhone and iPad

Sudoku is a logic game with a Japanese name that has recently exploded in popularity.
In order to complete the puzzle, you must fill each cell with a number between 1 and 9, inclusive, such that no number is repeated in any row, column or 3x3 box.
In a solved sudoku, each row, column, and 3x3 box contains all the numbers 1 through 9.
Each puzzle has only one solution.
This game has 3 levels to play: easy, medium, Difficult. Every time the player restarts the game, a new data table is generated and the player can play with a lot of different tables.
In order to win, players must have a clear strategy. If you enter the wrong number in a cell, the player can clear them away and fill others