Android phones can be tracked by battery use alone
A smartphone utilizes more power the further away it is from a cellular base and the more obstructions are in its way as it reaches for a signal.
According to a new study from Stanford University and researchers working for defense contractor Rafael, trackers may know where you are by measuring small changes in your battery power. Thus, tracking can still be possible even without using GPS or Wi-Fi data.
The researchers designed an Android app to measure these changes in battery use which over time allowed them to locate phones with up to 90 percent accuracy.
"The malicious app has neither permission to access the GPS nor other location providers (e.g. cellular or wi-fi network)," the team - Yan Michalevsky, Dan Boneh and Aaron Schulman, from the computer science department at Stanford University, along with Gabi Nakibly, from Rafael Ltd - wrote in their paper. “We only assume permission for network connectivity and access to the power data. These are very common permissions for an application, and are unlikely to raise suspicion on the part of the victim.”
The study used an app called PowerSpy but this battery use data can be obtained from more than 179 apps available on the Google Play store.
"This information is considered harmless and reading it requires no user permission or notification", the study states. "We show that by simply reading the phone's aggregate power consumption over a period of a few minutes an application can learn information about the user's location."
Android users need not to panic just yet. This technology could be used to track the locations of someone whose movements are known. It could presumably be of use to law enforcement agencies tracking the movements of known criminals.