Camera apps seem to get most of the attention from iPhone users, probably because there are a lot more people taking stills than video. The iPhone does have very capable video features, and some third parties seem to have outdone Apple when it comes to creating and editing videos you will want to share.
Videon is a perfect example. This US$2.99 app lets you shoot video as well as edit out those bits that should be left on the virtual cutting room floor. Videon's feature set is complete, with a nice-looking digital zoom, multiple resolutions and aspect ratios, adjustable frame rates for slow motion, independent focus and exposure points, and the ability to take a photo while you are recording