Amazon has patented a system to unlock your smartphone by recognizing the shape of your ear, when you raise the device up near your face to answer a call.

The patent, explained by our friends at PatentYogi in the video above, describes the use of a photo of the user’s ear, snapped by a phone’s front camera.

Just like matching up fingerprints with those from a database, this technology could help you log in to your phone without having to enter a passcode or pattern.

The human ear is said to be as unique an identifier as a fingerprint, so you can rest assured that your phone will work with your ears only.

In addition to authentication, the method could also be used to dynamically adjust speaker volume by determining the distance between the phone and the user’s ear.

The upcoming version of Android adds system-wide support for fingerprint recognition. It’ll be interesting to see if Amazon’s patent finds use in its next generation of Fire phones as a differentiating authentication feature.

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