Though the iPhone's camera is already top-notch, photography fanatics certainly could use more features. CameraTweak delivers. Advanced Mode for photos and videos lets you swap out the exposure and focus elements and replace them with separate reticles. Time Lapse mode for photos lets you take a series of shots over a certain amount of time. Timer mode for photos creates a built-in timer on your iPhone, and Custom Frame Rate for videos lets you adjust the frame rate.