But you can also scan a fingerprint without any special hardware. The Onyx, from Diamond Fortress Technologies, uses the camera on your smartphone. Free demo apps are available for both Android and iOS.
We're all used to talking on our phones, and, more recently, talking to our phones. What's more natural than to use that for authentication, as well?
Agnitio's Kivox platform allows app developers to do just that.
And, in case you're worried about criminals secretly taping your voice, Agnitio claims that its patented anti-spoofing technology caught 97 percent of spoofing attempts — while their competitors caught none of them.
Another benefit of their platform is that the software is resident on the phone and doesn't require an Internet connection.
The beta release of AppLock by Sensory is in the Google Play store if you're looking for an application that uses your phone's camera to see your face.
The app's security setting have a "liveness" mode for extra security, to keep the badguys from trying to spoof your face with a picture.
For even more security, the app can also check your voice.
Did you know that the shape of your ear is unique?
Did you know that's there's an app that reads the shape of your ear where it touches the screen?
It's called Ergo, and it's available now on Google Play from Descartes Biometrics.
And it's as easy to use as lifting your phone to your ear. Which you do all the time, anyway.
But it only has a rating of two-and-a-half stars, and reviewers complain about not being able to get it working.
So put this into the "not quite yet" column.
No, it doesn't draw blood. The VeinID from Hitachi uses infrared light to painlessly scan the veins inside your finger.
The scanner is already used at ATMs in Japan and Poland, and Barclays plans to deploy it this year in the UK.
According to the company, it's difficult to spoof because it doesn't read the exterior of the finger, but the inside, and the false rejection rate is lower than with fingerprinting.
It takes about a second to do the scan and authenticate someone.
Worried about bad guys chopping off your finger? Don't be — according to the company, dead fingers have no blood flow, so wouldn't be readable by the device.
Yes, there are consumer devices that read brainwaves. Unfortunately, none of them can be used as authentication devices out of the box just yet.
The Emotiv Insight, for example, is scheduled to hit the market this March, after raising more than $1.6 million in a successful Kickstarter campaign.
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