What are you to do in a world overrun by evil physics-beasts? Take the fight to them with your "slingshot-esque gift" of course. The odds are not in your favor, but you are David., the chosen polygon with the rainbow slingshot thing. At least it'll be a good fight.
David. is basically a boss-rush game. Each level has a new monster to battle, all of them a jumble of geometric shapes with new ways to attack you. You simply have to run and jump around the map while using your trusty slingshot to slay the beast with the power of physics. It's a very simple game, but the gameplay is well-executed and engaging. It doesn't really matter that there are no high-resolution textures or dynamic shading. David. is good at what it does.
The game is on sale for $0.99 (regular price $1.99) in celebration of its arrival on Android. There are no in-app purchases at all, so a buck and it's yours forever.