If you're looking for a great way to train your brain and have fun at the same time, Killer Sudoku is for you! This free app combines two of the most interesting activities: solving puzzles and working out math problems. The rules are very simple and you don't need to have any previous knowledge of math or logic to play the game. All you need to know is how to count and add up numbers. And if you're up to the challenge, you can even find a way to solve the puzzles in the most complex levels.

The game consists of different levels of difficulty that are designed to challenge you in different ways. The first levels are very easy and don't require any mathematical knowledge.