Featured in Chapter 3 of iPhone in Practice by Bear Cahill published by Manning Publishing.
Using your camera (iPhone only) or your Photo Album, pick an image and decorate it with stock images. Drop them on, drag them around and then email them to a friend (or take a snap shot by pressing the home and power buttons at the same time).
This app demonstrates the use of UIViewControllers, UIButtons, UIImages and email (including attaching files to email).
Chapter 3 of "iPhone in Practice" takes the reader step-by-step thru creating this app.
Read more here: http://brainwashinc.wordpress.com/iphone-dev-book/