Parents' outrage after girl flashes her naked crotch under graduation gown for high school yearbook photo

Of all the apps to be a success, this has to be one of the most improbable - yet unsurprising.

The X-Ray augmented reality app lets you see what catalogue models look like wearing just their underwear.

Users put their iPad or smart phone over the image of the model wearing clothes and it replaces it with a picture of how their bodies really are underneath.

The app does not actually carry out an X-Ray but uses augmented reality to approximate how each person looks.

It has been a huge success and been downloaded 75,000 times in five weeks with one million impressions on Twitter.     More Read