Facebook Friend Suggestions and Privacy Porosity (via Android IRL Friends?)

A few months ago, my wife came to me asking how Facebook would know to suggest a couple of people that she had spoken to professionally on her phone. I asked if they had been in the same location, or if they were in her contacts, or if you had mutual Facebook friends. “Maybe, yes”, and “No”, and “No” were her replies. I checked her privacy settings, and sure enough the OS privacy settings indicate that , and I think that . We talked it through, and I couldn’t find anything online about how this could be happening, but we also didn’t know the nature of the other people’s phones.

Then just the other day, I got a friend suggestion for a person that I had spoken to on the phone and texted with. We had also been in the same location a number of times. And we don’t have any direct mutual “friends”.

I do know that this person uses an Android phone, and what little research I did do, indicates that their is more porous access to contacts, as well as phone logs.

I would love to know more about this. My wife is definitely not a person who gets too wigged out by Google/Facebook/whatever creeping into privacy, but this has definitely gotten her attention.