Video Camera for iPhone by i4software is a video studio in your pocket. It allows you to switch between front and rear cameras while recording and snap photos while recording. For those looking for a professional level of control, Video Camera also lets you manually control exposure, focus, and white balance via a triple tap.
Apple has filed a patent to use the accelerometer and gyroscope in conjunction with the video camera of your device to improve image stabilization. The three core features could work together to hugely improve the look of your videos.