Another great Broke Indie Guy game
Dartle is fantastic little time killer. It has an easy learning curve, and the controls are simple. The complexities lie entirely in solving the puzzles, as it should for a game of its type. It's a good thing that all the levels are unlocked, getting stuck with no way to continue is not something I enjoy. All in all, a great game, well worth the dollar.
Oh yeah, for those of you looking for a way to make the game near impossible, try solving the levels in one go. You get to move the objects around after you place them if the light isn't going where you want, but I like trying to get it right on the first try. It'd be nice if there was an achievement for it, maybe something to consider in an update?