Severed digits can’t fool fingerprint scanners: Your fingers are safe

Severed digits can’t fool fingerprint scanners: Your fingers are safe. It didn’t take long for this news to hit the shelves after the reveal of Apple’s new iPhone 5s which features a fingerprint scanner as an additional layer of security. The HTC One Max also looks set to include the technology and undoubtedly this will become a standard for all smartphones to come. But how many of you have wondered if the plague proportions of ”apple picking” (smartphone theft) will soon mutate into ”apple and finger picking”?


               Keep your fingers off my fingers! / ©
Never fear, Hannibal Lecter, Leatherface and Norman Bates are not likely to get into the black market for stolen smartphones and tablets anytime soon. Despite their penchant for collecting various body parts, we have been assured that the iPhone 5s fingerprint scanner won’t work with a dead finger. No one has tried this out as far as I’m aware, but we’re happy to take their word for it, and spread the word to any would-be phone- and finger-thiefs.

The reason a severed finger can’t fool the scanner is twofold: the technology relies on both capacitive technology (where the body’s slight electrical current is transmitted to the device) and radio frequency (RF) waves to function. The RF waves are the clincher here: these waves penetrate the outer layer of the skin (and any dirt or scars) to read the living tissue underneath, where your nice clean fingerprint lives. So there’s no chance a chopped-off digit will still work.


Good news: all things should remain where they are. / © Apple

Even with a suitably battery-charged finger, any light-fingered thief would then also need to bypass your other security measures, be they a password, PIN- or pattern-lock. I suspect if someone had just relieved you from the ability to count to ten you’d be pretty unwilling to offer up that information, so chances are this added layer of security will remain exactly in the place it was always meant to be. So you can hold on tight to your iPhone, and your fingers.