Web companies can track you — and price-gouge you — based on your battery life

In Online tracking: A 1-million-site measurement and analysis, eminent Princeton security researchers Steven Englehardt and Arvind Narayanan document the use of device battery levels — accessible both through mobile platform APIs and HTML5 calls — to track and identify users who are blocking cookies and other methods of tracking.

But the takeaway isn't just that you might be tracked based on your "leaky battery" — but that companies might change their prices based on their guess that you'll pay more because you're running out of juice. For example, Uber's head economist Keith Chen has mooted future version of the app that jack up the prices if your phone is about to die).

He adds that companies can use information about battery life for purposes beyond online tracking and targeting. "When battery is running low, people might be prone to some — otherwise different — decisions," he writes, referencing a recent article about Uber. (Keith Chen, Uber's head of economic research, told NPR in May that people are more willing to pay higher fares for rides when their batteries are nearly drained — but Chen also said the company doesn't take that information into account when setting prices.)

"Even most unlikely mechanisms bring unexpected consequences from privacy point of views," Olejnik writes. "That's why it is necessary to analyze new features, standards, designs, architectures — and products with a privacy angle."

Online tracking: A 1-million-site measurement and analysis [Steven Englehardt and Arvind Narayanan/Princeton University]

Web Companies Now Track Visitors Based On Battery Life [Wendy Davis/Media Post]

(via Super Punch)

(Image: Low battery, Martin Abegglen, CC-BY-SA)