4 stars: Exactly what it says on the tin. By far what seems to me like the most polished and least annoying of water sort games. I prefer playing offline to avoid unprompted (and unwelcome) ads, but I'll watch one for the extra cup when I get very annoyed at a harder puzzle. Fairly relaxing and challenging enough to get the mental gears spinning. Not 5 stars because... wifi being on means an ad pretty much every board.
3 stars: Fun game! The only reason why I'm not giving 5 stars is because there's something wrong with the saving. I play several levels and exit the game only to find that none of my progress is saved and I have to play the levels again. Sometimes this happens multiple times and I can't progress through the levels! This is very frustrating!
2 stars: I really love this version of the water sorting games but I can't get anything to work except the cups. I can't click on anything else. There's been levels I wish I could get another cup or restart but the buttons to do so don't work.
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