Ziggurat is an 8-bit-inspired survival game for iOS, set during an alien apocalypse. It's the project of Action Button Entertainment founder and director Tim Rogers, a Bay Area transplant recently nominated the Most Interesting Man at PAX Prime, and a regular contributor to geek-centric content farm Kotaku.
The story: Aliens have just wiped out humanity, and you are the last man standing. Literally standing: You're atop a ziggurat, above the clouds, armed with one BFG-like firearm, making a last stand. You shoot by tapping, charge by holding the lower portion of the screen, and fire when releasing. The longer you hold the charge, the more velocity, size, and explosive force the bullet will have. Rapid taps cause small bullets to piddle out, but that technique has its purpose, primarily when you're fending off multiple aliens in close quarters and quick succession. Aim by swiping right and left toward the bottom of the screen.
This iPad game is inspired by the 8-bit visuals of games of yore, and it's also supposed to feature a frenetic 8-bit (or "chiptune") soundtrack. However, I could never get the sound to come through on an iPad 4 running iOS 7. And before you ask, yes, I checked to make sure the iPad wasn't muted and that audio came through on other installed apps. That's a ding, since the soundtrack is one of the most-hyped elements of Ziggurat.
The relatively elementary gameplay mechanics may lose casual gamers' attention. But competitive core gamers will keep coming back to hunt the trickier alien types that come along when you survive for longer periods of time. See if you can make it far enough to spot a purple alien.