5 stars: I love spending my free time in this app, some problems are challenging but when you solve them its very satisfying.
5 stars: An exceptional brain exercise. I highly recommend it.
4 stars: It is fun so far, but it can be irritating when the question has multiple reasonable answers or when they give too little information. One level had 2 interweaved sequences ultimately asking you to find the third term only given the first 2 and another with 3 different reasonable solutions depending on how you split things up. It would be nice if the solutions were unambiguous even if the problem is difficult.
3 stars: Too many of the puzzles are not mathematical and involve spotting strange manipulation of digits and performing unconventional operations. I'd also like to point out that puzzle 161 is incorrectly written, so cannot be solved.
2 stars: For those who are new to math puzzles it's a tiring experience to solve. Hints are behind ad & puzzle are without any description. So to understand new type of puzzle (changing format) you'll have to see ads and for someone new like me it becomes annoying to see ads, after each new type (new format) of puzzle is given to understand it you'll need to watch ads.
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