iphone photo making funny faces with you pictures

ok a few months ago i saw the 2.0 video and they showed this cool thing you can do with your pictures on your iphone you can pick a picture you have on your iphone and move you finger qaround on the face and make funny shapes and move the face around and to put the picture back to normal all you had to do was shack the phone ok i downloaded 2.0 but cant seen to find how to do this ??? any help?? thanks