AcceptableCells
At its best, CrossCells feels like an inductive-reasoning "expansion pack" on puzzles like sudoku and picross. Like the other 'Cells games, it incorporates multiple mathematical mechanics, and plays their hints off one another. And as I worked through its later puzzles, I felt very satisfied with their logical tightness.
But while CrossCells is pretty satisfying when it "works," it just as often "doesn't." Whether because I hadn't learned its rules adequately, or because the rules weren't applied rigorously enough - I couldn't say, in retrospect - many levels felt like I had to guess to move forward. Only after following that guess for several steps would I know if I was on the right track.
CrossCells would really have benefited from a "try it out" system, like some picross games have, to follow a hypothesis for a while and then undo it if necessary. But, let alone that -- CrossCells doesn't even have a "reset" function. Its interface is as minimally-functional as can be.
(Made a bunch of wrong moves? To reset the puzzle, you need to exit to the menu and click the puzzle again. And the annoying water-ripple animations draw this process out to several seconds. Ugh.)
CrossCells shows mechanical promise, but just isn't quite friendly and sophisticated enough (both in UI and in its difficulty-ramp) to be very noteworthy. And it's pretty short, to boot.
Better than: Hexcells, SquareCells
Not as good as: Hexcells Plus, Hexcells Infinite
... but for a sale price of under $1: it's hard to go wrong.
Progress: Finished all 50 puzzles.