Favorite Photo Apps

Some of my personal favorite apps:

Photogene
Photoshop Mobile
SnapBox
Best Camera
Cool fx

Plenty of other apps are designed to make your shots better after you take them:

FX Photo Studio
Photo fx
Photo Lab
Photo Makeover
Perfect Photo
Camera Bag
ColorSplash
Camera Genius
Night Camera
Iron Camera
HDR Camera
Camera Plus

Apps to look for:

Photo Booth Classic Plus

Art Camera processes your shot into the painting style of various famous artists.

PhotoFunia offers a multitude of different scenarios into which you can put your own photos.

There are plenty of Photo Texting Apps, too

Nikon Learn & Explore is a photography tutorial right there on your iPhone.makes a four-shot strip of snaps in the old "photo booth" style.

Social Apps

Access your favorite photo storage sites with Flickr, Photobucket,
Pixelpipe and PicasaFoto

There are also a number of apps which facilitate the sharing of your images through social networking sites like Facebook and Twitter.