Very well designed – Killer Sudoku + Review

I’m sort of addicted to this app. Killer Sudoku is a pretty complicated game, requiring the player to keep track of many possibilities. This app provides a lot of useful aids. For each cage, the app provides all the sets of numbers that are possible for it, and you can uncheck sets as you eliminate them as possibilities as you go along. You can, of course, enter “possible numbers” as notes in each square, or across a selection of squares. You can select more than one cage and the app will automatically tell you the sum of all its squares. There’s also a “calculator” that allows you to enter an arbitrary cage size, and it tells you all the possible combinations. There aren’t very many killer sudoku apps on the App Store (I know of two for certain), but this is easily the best one. It offers many sets of puzzles as in-app purchases, in a wide range of difficulties; since the harder puzzles have lots of replay value (unless you have perfect memory, I suppose), then a few of these purchases will last you a long time.
Review by Why does this nickname have to be unique, anyway? on Killer Sudoku +.