Addidoku is new puzzle game that has some similarities to Sudoku, but is also very different. In each level, you are presented with a several numbers set in a broken up grid. The goal is to group the numbers so that they add up according to the rules of the game. Each number can only be in one group and each puzzle has only one solution.

So what exactly are these rules? Well, in each group of numbers, all of the numbers (except for the biggest number) must add up to the biggest number. For example, the numbers 3, 2, 6, 1, form a group because the sum of 3, 2, and 1 is 6. You can also pair numbers, like two 5's, because 5 equals 5. The numbers 4, 3, 5 do not form a valid group because 4 plus 3 does not equal 5.

Only numbers that are adjacent to each other can form a group. This means that if a number is diagonal to your group or separated from your group by a space, it cannot be added to your group.

That's it! The rules are simple, but the levels are challenging. Even though they're challenging, they're completely doable which makes the game extremely addicting. Because each level can be completed in a reasonable amount of time, you are always willing to play "just one more".

The Good

• Challenging
• 140 additional puzzles available as in-app purchase