On your iPhone or your iPod touch, when you press the Home button, there’s a nice little animation that takes you back to the home screen.

To create that animation, your iPhone takes a screenshot of whatever it is you’re doing, and uses it for the transition. Sounds innocent, right?

Not so much, says data forensics expert Jonathan Zdziarski (thank you, clipboard). The screenshot is presumably erased from the iPhone after the application closes, but is any digital file really gone after you delete it? Survey says no.

Forensics experts have mined for these screenshots, successfully recovering evidence against criminals accused of rape, murder, and drug deals. They can also recover data from the iPhone’s keyboard and web caches, too. In his presentation, Zdziarski also demonstrated how to bypass an iPhone’s passcode in order to own the device and access personal data. Time-consuming? Sure (it took JZ about an hour and involved a custom firmware build). Impossible? No. As with all things digital (and networked), your privacy is largely illusory. Time to go Don Draper on this one and just use Field Notes books, my stack of business cards, and the rotary dial. Read full article from TUAW.