Gizmodo: How Facebook Figures Out Everyone You’ve Ever Met. “Behind the Facebook profile you’ve built for yourself is another one, a shadow profile, built from the inboxes and smartphones of other Facebook users.”
“Shadow contact information has been a known feature of Facebook for a few years now. But most users remain unaware of its reach and power. Because shadow-profile connections happen inside Facebook’s algorithmic black box, people can’t see how deep the data-mining of their lives truly is, until an uncanny recommendation pops up.”
“Many people realize that smartphones track their locations. But what if you actively turn off location services, haven’t used any apps, and haven’t even inserted a carrier SIM card?
Even if you take all of those precautions, phones running Android software gather data about your location and send it back to Google when they’re connected to the internet, a Quartz investigation has revealed.”
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