TNW Apps just named their Best Photography Apps for iPhone, and ProCamera is at the top of their list:
Procamera is a nice alternative to Camera+. It’s a bit pricier but I like the immediacy of its interface a bit more than Camera+, which makes you wade through some attractive but unnecessary screens to get to some features. If you’re looking for an app to use when you’re whipping your phone out of your pocket to grab a shot quickly, Procamera has the edge. It also offers an unlinked focus/exposure system and White Balance locking to help you set your color tone.