AVFoundation is just great for those who want to get hands dirty, but there still a lot of basic stuff not easy to figure like how to save the pictures taken from device to
There is a lot to setting up the camera this way that you either aren't doing or aren't showing.
The best place to look would be at: AVCamCaptureManager.m in the the AVCam sample project; particularly setupSession and captureStillImage (which writes the photo to the library).