Sudoku-Master app for iPhone and iPad

This is a very popular game and now available on iOS.
The objective of this game is to fill a 9×9 grid with digits so that each column, each row, and each of the nine 3×3 sub-grids that compose the grid (also called "boxes", "blocks", "regions", or "sub-squares") contains all of the digits from 1 to 9. The puzzle setter provides a partially completed grid, which for a well-posed puzzle has a unique solution
There are 3 levels in this game: easy, medium and hard. Every time users restart the game, the new number patterns are generated
This version also shows the elapse time for users, based on this, users can know how long they use to finish each game.