Though it was a big hit back in 1979, Atari's Asteroids never really took off as a series. The franchise peaked with the 1987 release of Blasteroids; afterward, the original Asteroids saw years of ports, remakes, and regular appearances in retro compilations. There's only so much you can do to expand on a single-screen shooter, I suppose.

After recently releasing follow-ups to Yars' Revenge and Star Raiders, Atari is giving Asteroids similar treatment. This Thursday will see the release of Asteroids: Gunner, a free-to-play twin-stick shooter for iOS devices that boasts over 150 levels, three playable ships, and an extensive set of unlockable achievements.

Much of the original Asteroids' appeal lies in mastering its difficult control scheme, so I have to wonder if twin-stick controls will strip away the game's identity and turn it into a Geometry Wars clone. Also concerning: Gunner's in-game currency (which can be bought with real money, of course) is seriously called Space Bucks.