BBC News:
Android phones can be tracked without using their GPS or wi-fi data by studying their power use over time, a study has found.
A smartphone uses more power the further away it is from a cellular base and the more obstacles are in its way as it reaches for a signal.
Additional power use by other activities could be factored out with algorithms, the researchers found.
The key here is that a malicious app can track your movement without getting permission to access your GPS info. Just tracking your power usage can help malware track your location. [Hat tip, Rob Richman]
It’s important to note that the app needs more than access to your battery usage data: the study states “we assume the attacker has prior knowledge of the area or routes through which the victim travels.” The app/attacker can’t pinpoint your location without having some frame of reference and it appears that any such attack would be targeted against specific individuals, not the general public.
Still, the idea that this can be done is disconcerting.