A system called Pulse allows smartphones to send and receive data via fluctuations in the magnetic field created by a nearby electromagnet, opening the door to a range of possible uses in the future.
By installing a magnetic sensor in the compass app of Android phones and iPhones, this system could offer an alternative to the regular 3G, 4G, Wi-Fi and Bluetooth networks we normally use.
Vassilis Kostakos and his colleagues at the University of Oulu in Finland have built an electromagnet system to test the idea out. They showed that by encoding data and exposing it to a varying magnetic field, they were able to transmit anything between an electromagnet and a phone, from music to a web address.
Kostakos told the New Scientist that one possible benefit is that of security, particularly for payments: because transmission works at a maximum range of two centimetres, it minimises the risk of an eavesdropping attacker stealing money from a phone that is near enough.
The traditional near field communications radio signal used for phone payments can be read up to 20 centimetres away, making the chance of having money stolen more likely.
He added that other smartphone sensors could also be built to transmit information using magnetism. "With other sensors the efficiency of a communication depends on how quickly you can physically manipulate the sensed parameters. I'm not sure how well a barometer would work for instance – we need to quickly change air pressure to convey information which could be tricky," he said.
The team will be revealing more details about how the magnetic sensors can be put to use in September at the annual computing conference in Seattle.