Scientists at the Illinois Institute of Technology say they've developed a system dubbed SilentSense that uses a phone's built-in sensors to record the unique patterns of pressure, touch duration and fingertip size and position exhibited by a user interacting with a phone or tablet, NewScientist.com reported Thursday.
This becomes a unique signature that identifies the user, they said, and anyone whose usage patterns do not match would be locked out of the device.
"Different users, dependent on sex and age among other things, will have different habits in interacting," researcher Chen Bo said.
A smartphone's accelerometer and gyroscope can measure how much the screen moves when a user is tapping it, and can also pick up on the user's unique gait as they walk while using the screen, Bo said.
In tests SilentSense was able to identify the phone's owner with 99 per cent accuracy after no more than 10 taps, the researchers said.
To save battery power the software suspends its identity checking when apps like games are being used, the researchers said, but will automatically switch back on when more sensitive applications such as email or text messaging are activated.