While Apple has been slowly improving the iPhone Camera app over the three generations of software, other developers have taken it upon themselves to squeeze as much out of the camera hardware as possible.

This week, it’s Joby, Inc., makers of the Gorillapod flexible tripod, who have brought a free app called Gorillacam to the App Store. The Joby folks are photography experts and it shows with the packed feature set in Gorillacam.

Gorillacam brings much-needed speed improvements to the iPhone camera. You can take unlimited rapid-fire photos, up to 1.6 frames per second. Press and hold the shutter button and take as many photos as you want. Best of all, you can keep shooting while your photos are being auto-saved in the background — no more waiting to save before you fire away again.

The app also makes self-portraits a breeze, thanks to Gorillacam’s ability to turn the entire screen into a shutter button — press anywhere on the screen and you’ll snap a picture. For babies and animals, the 3-shot burst mode is perfect, allowing you to take three quick photos in rapid succession.

Joby has also included a self-timer with audible countdown notification, perfect for group shots or self-portraits, as well as a time-lapse mode to take multiple photos as fast as one second apart or as long as two minutes apart.

But that’s not all: Gorillacam has a grid overlay built in, perfect for lining up horizons or buildings (it can be turned on or off) as well as a bubble level to take steady, level shots every time in both vertical or horizontal orientation. You can also share photos without leaving the app, and Gorillacam even features helpful tips on how to take better photos from the iPhone.

Gorillacam is a free app that outpaces competing for-pay programs, and makes a perfect companion for Joby’s Gorillamobile for iPhone 3G hardware (but it’s not required to use Gorillacam). The only caveat is that Gorillacam only does still photos, not video (at least for now).