Physics is your friend. That is to say, forces related to physics like gravity are a small comfort for those of us terrestrially bound. For those flying around tiny clusters of super-dense planetoids, black holes and white holes while rescuing the occasional astronaut, physics can be a royal pain in the rear-end. Blast Off by Halfbrick Studios is a physics based puzzle game that combines action elements to provide a devilish challenge.

Blast Off uses a single-touch system, propelling your ship towards wherever you touch on the screen. Each of the game's puzzle-based levels uses a mix of stellar objects to act as obstacles while you attempt to rescue lost astronauts on your way to the exit. This is easier said than done as later levels require lots of finesse to accurately scoop up the wayward souls. For a truly sinister challenge you can attempt to complete levels using up the minimum of air and fuel to beat the developer's high score.

The graphics are kept simple with a chubby-cartoonish 3D design to the ship and astronauts. Content is minimal, with 45 available missions that will keep you busy if you positively have to out-do the developers and three maps for the endless mode.

Blast Off is a simple, challenging puzzle game that's uncomplicated by harsh rules, but not harsh gravity. Unless you're truly dedicated to perfecting each level the game is bite-sized and easy to consume, but casual gamers will appreciate the lack of pressure and instantly understandable gameplay.