It never fails to amaze me how inventive some people can be.
A hundred years ago camera film was not the plastic and celluloid of today but plates of metal or more commonly glass.
Well what is the bag of an iPhone 4 & 4s made of? Glass!
Yes you guessed it, some very clever people have cleaned up the back glass, coated it in a photographic light sensitive solution and used the iPhone as a piece of film to produce a original works of art.
Developing the image must have been fun, working in total darkness painting developer onto the back of the phone with a paintbrush.