Security experts detect shady software that can use your smartphone's unique battery signature to sniff out your online activity.
Software that lets websites check the battery life of your mobile devices could also be compromising your privacy.
Privacy researchers have pointed out before that the HTML 5 battery status API, a web standard intended to allow sites to serve up low-power version to phones running out of juice, could also be used to identify specific phones by their battery usage fingerprint, reported the Guardian on Tuesday.
Even more alarming, researchers from Princeton University have found software currently running on the internet that is doing just that. In a paper released in July, the researchers said they observed two scripts using the battery API that could "fingerprint" a specific device and track it on the web.
The researchers were looking into online tracking and collected data from the top 1 million websites in January 2016.