A new study has found the location of Android phones can be tracked by measuring aggregate power consumption.Researchers have found that over a period of a few minutes an application can learn information about the user’s location, having developed an Android application, PowerSpy, which collected data about power consumption.
The phone’s location affects the power consumed by the phone’s cellular radio, the study states, with the closer the phone is to the base station and the fewer obstacles between the two, the less power the phone will consume.
The study describes how location is related to signal strength, and how signal strength is related to power consumption, demonstrating how obtaining access to power measurements could leak information about a phone’s location.
“We emphasise that our approach is based on measuring the phone’s aggregate power consumption and nothing else,” researchers Yan Michalevsky, Dan Boneh and Aaron Schulman from Stanford University, and Gabi Nakibly from Rafael, state in the paper.
“We do not read the phone’s signal strength since that data is protected on Android and iOS devices and reading it requires user permission.”
Reading the phone’s power consumption, by contrast, requires no special permissions the study notes, with there currently being over a hundred applications in the Google Play Store accessing files reading aggregate power consumption.
“While most of these simply monitor battery usage, our work shows that all of them can also easily track the user’s location,” the study states.
The authors note that with more data they believe the approach can be further improved and “used to obtain even more information on the phone’s location”, stating the work suggests more security modelling needs to be carried out before giving third party applications direct access to sensors.
