This is a surprisingly enjoyable brain teaser, casual, puzzle like game where you make fractals of one color. A fractal is a diamond of 7 tiles / cubes / gems / whatever. 2 on the left, 2 on the right, 3 in the center. How do you arrange them? You simply click an empty space on the grid or the border of the level. When you click that empty space, the spaces around it push out with whatever color gem you have next in your cue. Let's say green gem in your cue you will push out in all directions shifting all the gems in all directions 1 space over. Like pushing lines in 6 directions. You only get a certain amount of 'pushes' per level. To beat a level you need to get X amount of points. When you make a fractal, other gems appear in the level, which may lead to a chain of fractals or mess you up. Sometimes you need to think 2 or 3 moves ahead and when different colored gems get involved you need to make sure one move doesn't mess up something else you've been planning.
The campaign won't take more than a few hours, but I can see there being replay value in the way that Tetris is replayable. While the score isn't a big focus of the game, it still gets your brain going. There's no pressure or time limit, its soothing. The puzzle mode has several continuous puzzles.
Eventually the game throws different kinds of tiles your way. If those special tiles are in your fractals, you will get their bonuses. Things like adding more tiles to your cue, exploding all connected tiles of the same color, pushing tiles apart from the fractal and so on. It adds a needed level of depth.
Luckily there are two other modes, arcade and puzzle. Puzzle mode has you completing objectives such as making a triple fractal in X number of pushes or clearing all of the diamonds. It is a nice diversion, but not the meat of the game. The arcade is more of a time attack to get as many fractals in a limited amount of time. There are time tiles that will add to the clock when they're in a fractal.
Fractal is not for everyone. Its very much a touch screen mobile game, but it is fun and engaging for a while.