4 stars: I like it more and more as I play. You can use all of the regular tricks and strategies to solve the puzzles, and the added boxes with sums adds another neat way to solve. Easy and medium levels I'd say are easier to solve than a traditional Sudoku, but the hard and expert levels are definitely a challenge! If you like puzzles and basic math, you'll enjoy these! (Expert level puzzles take me between 20-40 minutes!)
3 stars: (Increasing to 3 stars from my last review, as I figured out how to change the colour palate so it's easier to look at.) While I appreciate that they have to have ads to make money off the app, interrupting you in the middle of a puzzle multiple times with video ads is absurd. An ad at the end of solving a puzzle I would understand, but not 3 times while I'm still working on it!
3 stars: Love the game. My only complaint is that you only get 3
2 stars: Great implementation. Please allow disabling hints - or make them harder to activate. Wasted a few puzzles by accidentally hitting the hint button. Edit: it seems to have a limited pool of puzzles. I've now gotten the same one 4 times, including twice in a row. Needs a better method of generating puzzles.
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