Parents should talk to their kids about new image sharing apps that give a false sense of privacy.

Snapchat, released in 2011, and Facebook’s Poke, released on Friday, allow users to send images and videos to one or more recipients. The images “self destruct” and erase themselves 1 to 10 seconds after they are opened. But it’s still possible to capture the images before they are deleted.

The iOS platform that powers iPhones and iPods can save an image of any screen by simply holding down the home button and pressing the standby button at the top of the device. Snapchat and Poke can detect when a screenshot is made of a private image and notify the sender, but neither app can stop a permanent copy of that image from being made and shared.

And there are many other screen capture methods the apps won’t be able to detect.

One way is through “Airport Mirroring” – a feature that allows whatever is on an iOS screen to be transmitted, wirelessly, to an AppleTV or software running on a Mac or Windows PC. From there it’s relatively trivial to record the content on screen. Another method would be through “jailbroken” phones that allow the installation of screen capture software usually barred by Apple. And then there’s the low tech method of recording one device’s screen with the camera from a second one.

Many in the tech press have labeled this new genre of messaging applications as “sexting apps” given their primary feature is deleting images quickly after they are opened. According to a recent profile in All Things D, a majority of Snapchat’s users are between 13 and 25 years of age and are sending a whopping 20 million “snaps” a day. That growth was certainly noticed by Facebook, with rumors that CEO Mark Zuckerberg was part of the small team of coders who built Poke in just 12 days.

As this segment of social networking grows, the best advice for kids and teens to stay safe is also the oldest: if you want something to stay private, don’t share it.

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