A team of Indian-origin researchers in the US has made it possible to essentially let their bodies act as the link between the card or smartphone and the reader or scanner, making it possible to transmit information just by touching a surface.
The prototype, developed by Purdue University engineers, doesn't transfer money yet but it's the first technology that can send any information through the direct touch of a fingertip.
While wearing the prototype as a watch, a user's body can be used to send information such as a photo or password when touching a sensor on a laptop, the researchers said.
"We're used to unlocking devices using our fingerprints, but this technology wouldn't rely on biometrics - it would rely on digital signals. Imagine logging into an app on someone else's phone just by touch," said Shreyas Sen, a Purdue associate professor of electrical and computer engineering.
"Whatever you touch would become more powerful because digital information is going through it," Sen added in the study published in Transactions on Computer-Human Interaction, a journal by the Association for Computing Machinery.
Shovan Maity led the study as a PhD student in Sen's lab.
The technology works by establishing an "internet" within the body that smartphones, smartwatches, pacemakers, insulin pumps and other wearable or implantable devices can use to send information.
"These devices typically communicate using Bluetooth signals that tend to radiate out from the body. A hacker could intercept those signals from 30 feet away," Sen said.
Sen's technology instead keeps signals confined within the body by coupling them in a so-called "Electro-Quasistatic range" that is much lower on the electromagnetic spectrum than typical Bluetooth communication.
This mechanism is what enables information transfer by only touching a surface.
Even if your finger hovered just one centimetre above a surface, information wouldn't transfer through this technology without a direct touch.
"This would prevent a hacker from stealing private information such as credit card credentials by intercepting the signals," the authors wrote.
Credit card machines and apps such as Apple Pay use a more secure alternative to Bluetooth signals - called near-field communication - to receive a payment from tapping a card or scanning a phone.
Sen's technology would add the convenience of making a secure payment in a single gesture.
"You wouldn't have to bring a device out of your pocket. You could leave it in your pocket or on your body and just touch," Sen said.
The technology could also replace key fobs or cards that currently use Bluetooth communication to grant access into a building. Instead, a person might just touch a door handle to enter.
The researchers believe that the applications of this technology would go beyond how we interact with devices today.
"The ability to transfer information through your touch would change the applications of that big touch screen," Sen said.