The app has a few typical (and not-so-typical) features you'd see in a restaurant or store chain app, such as a store locator. Then it has something new called "Moo Vision," which has that added augmented reality flavor. You point your iPhone's camera at the lid of one of several qualifying pints of B&J's, and, after a few seconds, you're staring at the lid with an odd 3D image atop of it.
I'd love to show an example of this first-hand. The problem is, I don't eat Ben & Jerry's ice cream. So, short of looking like a real loon in the frozen food isle at the local grocery store, it wasn't happening. However, I had a little luck fooling the app by pointing it at an image on my laptop screen of one of the qualifying flavor lids. Give it a try yourself (only Milk & Cookies in the image works).
I'm all for doing neat things with the iPhone camera, compass and gyroscope, but this usage appears to be severely lacking. It's more fun trying to see if you can trick the camera with a web image than it is to actually see it in full action.
The Ben & Jerry's Scoop of Happiness app is currently available and free in the App Store.