App Name: Sudoku Mega Bundle [iOS Game]

Cost: Free

Developer: Diego Acevedo

App Market: Download Page

Description:

Sudoku Mega Bundle has 38 unique game modes, some of which have never been seen on the AppStore before! Including Killer, Jigsaw, Skyscrapers, 16×16, Samurai, Word, Duplex, Anti X, Lucky Seven, and many more!

The game has leaderboards, achievements, difficulties settings, easy and smart note taking, saved games, and appearance customization. Finally it is free, universal and no in-app purchases.