It's powerful by itself, but even more so if you use it in conjunction with it's web interface. When launching the app, you are presented with a grid on the screen which looks something like the Latitude and Longitude lines on a globe. As you move and tilt the ipad, the grid moves around on the screen (actually it stays stationary, you are just moving around within it).
Start taking pictures and the app will automatically take a picture every time you move it to look at a portion of the grid that is blank. As the pictures are being taken, the grid starts to fill with the photos. Spin 360 degrees, tilt up and down and capture the whole room or space. (also works great with landscapes). After you finish with all the pictures, click done and the app will stitch all the photos together.
You can view it on the device in a variety of formats, flat, and in 3d where you can pan back and forth, up and down and it all looks like one photograph. You can export the image as a flat jpeg to the ipad's photo gallery (where you can email it to whomever you like). You can also upload it to their online gallery (which I believe you need to create a free account to access)
When you take the photo, the app uses the built in GPS and compass to determine your location and which direction you are facing. When you view it online as a single stitched image where you can pan back and forth, a little compass rose icon on the screen shows you which direction you are facing. And a google map to the side puts a pin in the location the photograph was taken.
These were two of the features I was most impressed with. By using the online interface, I can immediately tell not only where the photo was taken (exact location, can be beneficial on greenfield sites where there is no reference point, or within big buildings if you forget to record the room number). The compass rose is also very valuable as it shows you which direction you are looking. Unless you are the person who took the photos, you probably have no idea which direction they are facing, and would need that person to explain it to you.
The web interface also includes 3 different viewing options, first the single flat jpg, second the interactive stitched panorama you can pan through, and third, a stereo 3D view, which is neat in itself.
For the $.99 this app cost, it was more than worth it.
The website contains a gallery from other users, most upload panoramics they take on trips and vacations. The algorithm that stitches the photos together is really good (although not perfect).
Here is their website: http://occipital.com/360/app
