Challenge your mind with this great "Sudoku Genius" Game

https://play.google.com/store/apps/details?id=com.orionz.sudokugame

It has an easy and nice interface. It is a game and generator simultaneusly.
There is not any list with given puzzles. The puzzles are generated when you play.

How many levels are there in the game?

There are 5 levels in the game:

Beginner
Easy
Normal
Hard
Insane