Face Unlock, one of the flagship features of the newly released Android 4.0 "Ice Cream Sandwich" mobile operating system, enables users to unlock their phones via facial recognition rather than a PIN code or by using other security credentials. But there might be a security risk involved, if recent reports are to be believed, as the feature can apparently be fooled by holding a picture of the phone's user to the camera.

The new feature works by recognising pre-registered faces, though questions were raised during the Ice Cream Sandwich keynote address when the phone of Matias Duarte, Google's head of user experience, struggled to identify him and unlock the phone possibly due to poor background lighting. A Google spokesperson said the feature would "only get better," highlighting that the technology was still in its infancy. The same representative also conceded that logging into the phone by using a photograph of the pre-registered owner "could" possibly also work.

Google acquired the technology used for facial recognition earlier this year when it purchased PittPatt, a startup company spun out of Carnegie Mellon University. The technology they developed uses "tools to search images for faces, determine if faces are the same person, track faces in video sequences, and pinpoint constituent landmarks in faces using a straightforward C-language interface." Similar technology has also been used in past research with some accuracy to predict social security numbers from pictures of people.

In response to comments on Twitter that the feature could be fooled by a picture, Tim Bray, who works on the Android platform responded "Nope. Give us some credit."  While there is no doubt that Google has much to refine regarding the new Face Unlock feature, these security concerns might still cause the search giant some embarrasment at a time when the mass media and consumers alike are showing heavy interest in the new Android release.