Although the new iPhone 4 sports a significant 5 megapixel upgrade to its camera application, many of us are still happily using our iPhone 3G or 3GS camera. Some are still using the iPhone 2G!

With each upgrade of the iPhone, the camera improves, but if you want better functionality to take better pictures on the iPhone, I recommend starting off with the free Camera Plus app [iTunes Link].

Side by side, you can quickly see that even the free version of the Camera Plus has more features than what you will find with the native 3G camera.

The 3GS gets a little better in that it has an autofocus feature, plus three megapixels of resolution. But these features don’t outshine what Camera Plus can do.

The free version of Camera Plus only offers a few post-processing tools – one for cropping images and another for black and white conversion.

Let us know what you think of Camera Plus and if it helps you take better pictures – and what other camera applications you find useful for the iPhone.