how to implement animation on shake effect in iphone?

I have imp开发者_StackOverflowlemented one simple application for iphone.now i want to implement some animation.

Example:i have selected one photo from the photo library.Then i want to animate selected portion from the photo using shake effect.

I have seen lots of application in apple store.But i dont know how to implement this functionality.

Maybe you are referring to the "wobble" effect? See how to create iphone's wobbling icon effect?