4 stars: it's great and time killer. it's various from easy to expert. Even, 6 Side Cube, really different from any. However, say a best puzzler, I pressed wrong button and unable to press undo, result in start over on certain puzzle. So, please add feature, Undo. It's not required, but an option. it can be set to turn on/off on menu for gameplay. Either way, they can set up it or not while playing.
4 stars: The app asked for my rating after only the first set of levels so that is the basis for this review. I only trace flows on three sides of a cube. It would be more challenging and cool to trace them on the surface of a a rotatable three dimensional cube. Then it could move on to tracing them on the surface of other polyhedra or tunneling them in three dimensions through the cube. This last might make an interesting VR puzzle.
3 stars: The game would get 5 stars for its fun factor if they added a button that allowed you to undo a single move, so that you dont have to restart a puzzle after you fat finger a line while trying to get a perfect. Another minor issue is i wish there was an option to say if a type of ad was relevant to you, getting way to many political ads and I play a game to escape that stuff.
2 stars: I like the game. However, I had over 25,000 stars and 405 hints from over two years of playing. I did have the Cloud Sync turned on, but when I had to factory reset my phone and reinstall the game, I lost all my stars and hints. Seems Cloud Sync doesn...