Alien Swarm 3D is a shoot 'em up game with aliens. You can control your ship with the tilt of your phone or tablet, and use the on-screen buttons to blast the aliens. There is an option to play with your eyes closed, which adds a bit of difficulty to the game. The game has four difficulty levels, and the harder the level is, the more points you get. There are also five different aliens to blast. There is no time limit, so you can play as long as you want. The bonus rounds will give you more points, so you will get a better score. There are five levels in the bonus rounds. You can play the game with or without ads. There is no in-app purchase. You can play the game on your phone and tablet.