Scrunch Yo Self is a stripped-down photo manipulation app that works okay, but only offers a very limited number of options. The core concept is about as far as the app goes, allowing you to squeeze and pinch photos of yourself or others to form strangely formed, manipulated images that can be shared on Facebook.
When you start the app, you have only one option -- to load an image from your library or take a new photo to work with. You can then start squeezing and pinching the screen or you can immediately share it to Facebook. The sharing options are very limited, only allowing you to upload to Facebook or save to your camera roll, so unless you only share to Facebook, you'll probably be doing the latter most of the time. The pinch function is also very limited, as there are no other editing or photo manipulation options in the app to work with. If you get tired of pinching and zooming the contents of your images, there just aren't any other options to move to.
If you want to scrunch your face or manipulate images with pinch zooms on certain areas, then Scrunch Yo Self works well for this. However, with a limited interface, only one sharing option, and few options for editing the images other than pinching them, there are plenty of other apps on the market that offer more.