Ask HN: I talk about something in rl and get ads on ig/fb. How do they do that?

[dvcrn]

That it's very creepy aside, I am wondering from a technical standpoint how they do that including the speed that it happens.

- I talk about something with friends, for example a pair of new shoes. I never search for shoes online and never online ordered. Next time I open instagram I get ads for new sneakers.

- I talk with a friend about depression and mental conditions, next thing I get ads for a new online counseling app.

This happens with friends using both Android or iOS. We are not on the same wifi network and don't talk about these things online through messengers. I don't have facebook installed (but have instagram and messenger). I am a somewhat cautious person and besides very rarely checking instagram or replying to messages barely open either app.

One theory is that someone at a later point searches for it online and through GPS approximation and social graph the network makes the link back to me. But besides that I have no clue. Always listening through microphones is a far stretch especially given security models and APIs on iOS.

[Hackbraten]

My guess is that it’s either what your theory says or pure coincidence. It’s a mathematical fact that the ads sometimes have to align with whatever your conversation topic is.

The chance of such alignment may be significantly higher than our intuition says, a bit like the birthday paradox counterintutively has a >50% probability of happening.

[dvcrn → Hackbraten]

I am aware of that theory but it just seems too on point to be just coincidence and bias. Especially because I am already aware of this happening I monitor what I get advertised so it's not like I am skipping things subconsciously that I don't care about.

The suggested ads take a full 180 turn depending on what's going on in my life. At first it's about jobs, then shoes, then about mental health, then about some concert I only verbally talked about (with bands I don't listen to).

Instagram ads are spot on, exactly what's currently recent in my life. There is no relation to the ads beside me talking about it.

[Nextgrid]

Your theory is entirely plausible and in fact I would expect no less from a creepy entity like Facebook.

Another option could be that you've searched or browsed content about this before so you were getting these ads occasionally anyway but didn't pay attention to them until you talked about it and now that ad stands out.

[sarcasmatwork]

They are listening via mic. Check permissions for your apps and disable mic.