Biometric technology could eliminate the need to carry a payment card or even a smartphone by allowing users to authorize payments with a fingerprint, handprint, face or retina scan. But the technology has had a rocky past, and each new product comes with new quirks. (Image: ShutterStock)
Attendees inspect Galaxy S5 smartphones on display during a Samsung Electronics Co. news conference on the opening day of the Mobile World Congress in Barcelona, Spain, on Monday, Feb. 24, 2014. Top telecommunication managers will rub shoulders in Barcelona this week at the Mobile World Congress, Monday, Feb. 24 - 27, a traditional venue for showcasing the latest products for dealmaking. Photographer: Angel Navarette/Bloomberg


PayPal may have spoken too soon when it announced support of fingerprint payments on Samsung's new Galaxy S5 smartphone. Fingerprint payments seem to be a touchy subject for Verizon, which has blocked the option, according to an analysis from Droid Life. (Image: Bloomberg News)


PulseWallet launched in 2012 using fingerprint technology, and later switched to palm vein sensors because the hardware was smaller and more appropriate for the application. The company predicts that eventually users will be able to wave a palm over a reader instead of touching it.
A customer tries out the new Touch ID fingerprint scanner on an Apple Inc. iPhone 5c during the launch at a Verizon Wireless store in West Valley City, Utah, U.S., on Friday, Sept. 20, 2013. Apple Inc. attracted long lines of shoppers at its retail stores today for the global debut of its latest iPhones, in the company's biggest move this year to stoke new growth. Photographer: George Frey/Bloomberg


Apple enables fingerprint authorization for iTunes and App Store purchases on the iPhone 5s, but it has yet to allow other developers to access the technology for third-party payment applications. The restriction gives Apple an advantage if it plans to incorporate biometrics into a broader payment system. (Image: Bloomberg News)
analysing hand with scanner


Quixter, developed by an engineering student at Lund University in Sweden, allows shoppers to scan their handprints to authorize payments on the school's campus. It has 1,600 active users, according to inventor Fredrik Leifland. (Image: ShutterStock)


PayTango is another biometric payment system thought up by college students. Four Carnegie Mellon University students created PayTango in 2012 with funding from Y Combinator. The technology lets users register two fingerprints to link to a payment card. (Image: ShutterStock)
A Discover Financial Services credit card is arranged for a photograph in New York, U.S., on Thursday, June 23, 2011. Discover Financial Services reported a second-quarter profit of $1.09 a share, on a tax benefit. Photographer: Scott Eells/Bloomberg


Discover began testing biometrics at its headquarters at the end of 2013. Its vendor, Natural Security, predicts that any customer-facing deployments are three to five years off because the U.S. is still in the process of implementing EMV-chip cards and contactless payments.(Image: Bloomberg News)


SmartMetric created a fingerprint-protected card that stores bitcoins offline, protecting the digital currency from hackers. The card has a built-in EMV chip, but it can't yet be used for payments. (Image: ShutterStock)
"Partners," a statue of Walt Disney and Mickey Mouse, sits in front of Cinderalla Castle at Magic Kingdom, part of the Walt Disney World theme park and resort in Lake Buena Vista, Florida, U.S., on Monday, Aug. 31, 2009. Walt Disney Co. said it agreed to buy Marvel Entertainment Inc. for about $4 billion in a stock and cash transaction, gaining comic book characters including Iron Man, Spider-Man and Captain America. Photographer: Matt Stroshane/Bloomberg

Walt Disney World

Walt Disney World's new MagicBand system, which enables vacationers to make payments and unlock hotel doors with a specially issued wristband, works in tandem with the company's existing biometric fingerprint scanning system at the entryway to each theme park. (Image: Bloomberg News)

Daon/Optimal Payments

Daon and Optimal Payments are pitching fingerprint and retinal scanning technology as an option for high-risk businesses to meet stringent Know Your Customer requirements. (Image: ShutterStock)

Zoom Tan

The patrons of Zoom Tan, who often visit the tanning salon straight from the gym without bringing a credit or debit card, were given the option to pay by fingerprint in 2012. (Image: ShutterStock)

Pay By Touch

The Pay By Touch system from Solidus Networks Inc. is long gone – the company entered bankruptcy in 2008 – but it won some significant clients in its short life. The grocery chain Piggly Wiggly Carolina Co. and the gas station chain Shell Oil Co. were among the fingerprint payment system's adopters.