Futuristic biometric schemes—think "I, Robot," "The Incredibles" or "Minority Report"—are jumping from the silver screen into the mainstream, and entrepreneurs and credit card companies are harnessing the technology in an effort to pry open the wallets of fretful online spenders.
And you thought biometrics was all about security.
How will biometrics help turn you become a more carefree impulse shopper? Unwieldy password schemes combined with jitters about security are dampening e-commerce, with consumers abandoning their online shopping carts on more than two out of three forays, according to a compilation of 22 studies by researcher Baymard Institute.
More than two decades after the Web's launch, only 5.8 percent of U.S. retail sales are transacted digitally, according to an August report from the Census Bureau.
Evidence of online insecurity grows daily, with hacks by groups like Anonymous and the Syrian Electronic Army and marquee victims from Apple to Nasdaq to Facebook to The New York Times. Biometrics experts say their technologies will put concerns to rest by adding new layers of authentication while improving the experience of users burdened with multiple logins and passwords.
While the fingerprint scanner on Apple's iPhone 5S raised the profile of physical biometrics and hopes for a bump in mobile commerce, developing technology is not stopping at physical factors like iris or facial geometry scans.
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The future is multimodal, according to Josh Alexander, CEO of Toopher, a start-up based in Austin, Texas. The best authentication systems will combine something you know, like a password, something you are, like a fingerprint, and something you have, like a mobile phone, he added.
Toopher, whose tools are used as a security layer by email marketer MailChimp and password automator LastPass, uses behavioral biometrics through mobile phones to map users' location, travel and payment patterns, and to let them automate their second layer. To create a seamless experience, Toopher's app lets users set up automatic log-ins at a particular location on a specified computer or mobile device.
Another start-up, BehavioSec, authenticates users by measuring the pressure, angle and speed of how they handle their computer mouse or swipe on their mobile devices.
"You can design the most secure system ever, but it comes at a cost," said Neil Costigan, CEO of Stockholm-based BehaviorSec, which is funded by the Defense Advanced Research Projects Agency (DARPA).
That cost can be password fatigue. In 2011, more than 60 percent of smartphone users were not using a PIN to protect mobile access, according to Jean-Noel Georges, a Paris-based analyst for Frost & Sullivan.
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That's why BehavioSec designed a system that runs entirely in the background, Costigan said.
"The whole experience is supposed to be completely transparent to the end user," he said. "The devices—Android, iPhone, Windows—are all great biometric devices without extra hardware. You don't need the latest edition of the newest phone."
DARPA is testing the technology to upgrade security on military computers, and several banks have also signed on with BehavioSec.
New York-based Socure scans social network accounts such as Facebook, LinkedIn and Twitter to authenticate users.
At the Finovate conference in New York last month, Socure CEO Sunil Madhu told an audience, "While it's easy for me to steal personal information about you and create fake accounts on your behalf or take over existing accounts, it becomes extremely hard when you factor in the network effects to go about identity-proofing that individual."
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How does it work? When a user fills out applications at a bank or other institution, Socure uses a proprietary algorithm to compare the data against information on social media and the broader Web. It then generates a credibility score used to accept or reject the prospective account holder.
Although German hackers figured out a way to hoodwink the fingerprint scanner on Apple's iPhone 5S, analysts are still optimistic that the feature will usher in more mobile spending.
"By associating the fingerprint with the Apple ID, we're going to spend more," said Alan Goode, the U.K.-based managing director of consulting firm Goode Intelligence. "It's all about the bottom line and making it more convenient."
Credit-card processors also are using biometrics to shore up security.
For example, 10 million South Africans now carry MasterCard debit cards from Pretoria's Social Security Agency that include fingerprint and voice signatures in their chips.
"It enables the consumers who historically have not had access to financial services [to open] an actual bank account," Kim Slate, MasterCard's vice president of emerging payments, said in a video demonstration. "They can use the card anywhere MasterCard is accepted."
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A wave of biometrics-fueled spending on mobile devices may not be right around the corner, however, and Noel at Frost & Sullivan does not expect a big uptick in transactions until 2018.
Further, some criticize the lack of flexibility in physical biometric devices, such as Apple's fingerprint scanner, because they provide no recourse if compromised.
"You can't change your fingerprints or the vein patterns in your hand," said Alexander at Toopher.
Still, the need for dependable online security is readily apparent. According to PriceWaterhouseCooper's latest State of Information Security Survey, corporations are reporting a 25 percent rise in breaches this year from 2012, and losses of $10 million or more are running 51 percent higher than in 2011,.
The right combination of body features, gestures and mobile tracking sensors could turn those losses into bulky online carts and lengthy sales receipts.
—By Ken Schachter, Special to CNBC.com