We’ve seen lots of Android apps that offer inventive ways to secure your smartphone, but I don’t think any of them are as interesting as Ergo from Descartes Biometrics. Ergo lets you unlock your smartphone using the unique geometry of your ear, so gaining access to your device is as easy as placing it against your face.

Using biometric authentication, Ergo detects and records the shape of your ear as you hold your phone against your face — just as you would when taking a phone call. It’s “non-evasive and non-distracting,” and because the geometry of your ear is unique, it’s incredibly secure.

“An individual’s identity is verified as an authorized operator by combining a physiological biometric, data derived from direct measurement of the ear, with a behavioral biometric, data derived from the physical action taken by a person as they raise their smartphone to their ear,” Descartes Biometrics says in its description.

Ergo allows you to forget PINs and passcodes that are time-consuming and easily forgotten — and easily guessed. But how reliable is it?

Well, I’ve been testing it on my Nexus 5, and I must say it’s very impressive. Unlocking your phone by just holding it up to your face is strangely satisfying — like using Touch ID on the iPhone 5s for the first time. The only problem is, I can’t get Ergo to work properly all of the time.

I’ve set it up twice now — the first time I did it, I couldn’t get the unlock to work at all — but now it works most of the time. You have to make sure you lift your phone in the same way each time, and then you have to make sure your ear is always lined up properly, too.

It can be frustrating at first — particularly when your phone vibrates in your ear to tell you you’re not doing it right — but once you’ve gotten the hang of it, it’s terrific. It’s also worth noting that you can adjust the strength of the security and make it more “relaxed” for more successful scans each time.

If you’d like to try out Ergo for yourself, it’s available to download now from Google Play, priced at $3.99.

• SourceGoogle Play