Puzzle Cube

Each turn moves a whole row or column of nine cubes, and the puzzle is to bring every face back to one color.

Here every little cube is its own piece, and the cube keeps track of each turn, so you can really solve it: drag across a face to turn that row or column. A tap scrambles a solved cube, or turns a scrambled one back to solved, one layer at a time. Tap while it turns and it pauses once the turn in progress lands, so you can take over by hand: your own move ends the automatic one, and the next tap starts again from there. Solving it by hand earns a hop and a chime. The cube has about 43 quintillion arrangements, yet any of them can be solved in 20 moves or fewer when a half-turn counts as one move.