“Facebook has gotten more aggressive in its use of smartphone location data in the last year”

Kashmir Hill:

with creepy accuracy the “people we may know” has surprised, delighted, and horrified its users for years. While the magic sauce behind friend suggestions has always been a bit mysterious, it now includes some potentially unsettling information. Thanks to tracking the location of users’ smartphones, the social network may suggest you friend people you’ve shared a GPS data point with, meaning your friend suggestions could include someone whose face you know, but whose name you didn’t until Facebook offered it up to you.

Last week, I met a man who suspected Facebook had tracked his location to figure out who he was meeting with. He was a dad who had recently attended a gathering for suicidal teens. The next morning, he told me, he opened Facebook to find that one of the anonymous parents at the gathering popped up as a “person you may know.”

The two parents hadn’t exchanged contact information (one way Facebook suggests friends is to look at your phone contacts). The only connection the two appeared to have was being in the same place at the same time, and thus their smartphones being in the same room. The man immediately checked the privacy settings on his phone and saw that Facebook “always” had access to his location. He immediately changed it to “never.” (He also did not want to reveal his identity for this story.)