One thing I really like about Sudoku is how it manages to work my brain while still being fun. So when I came across Sudoku Unlimited, I had to give it a try. What's $2.99, right?

I think what I like best about Sudoku Unlimited is how simple it is. Not the game, mind you. Sudoku can be very difficult. But the layout of the application is simple and easy to understand. You're provided with just enough options to give you some control over the game but not so many it overwhelms you.

For instance, when working on a puzzle, you can make notes in each of the open boxes for numbers that you think might fit there, just like you would on a piece of paper. Also, there are five different settings that provide you with beginner-level ease to you-have-to-be-nuts difficulty. Plus, you can change the way the board looks with three different skins.

If you're brand new to the game, you can select the "Auto-fill" function which automatically enters in all the possible numbers that can go in the open boxes via the Notes function. This is a great way to get familiar with the game. You can also "Clear Notes" and get a Hint if you're stuck.

I enjoyed this Sudoku game. And while there are several other games like this on the App Store--some of which are free--this one brings a sense of completeness to the plate. If you like Sudoku, this one's worth the few bucks.