The built in panorama tool that got included with iOS 6 is pretty nice and lets you create some great shots. When you first choose the panorama option (Options > Panorama when camera app is open) you’ll see an arrow which shows that you should move your phone from left to right.
But if you ever feel like changing things you can tap on the arrow and it will change direction! You can then move the phone from the right to the left.
Another nifty feature is that you can stop capturing the panorama at any time by pressing on the shutter button a second time before the panorama has been completed. And don’t forget you can also use the volume up button to take a photo/snap the shutter button.