There is literally no way for a non-active app on iOS to record without a red bar at the top of the screen. The only way that IG could possible get away with this is by somehow detecting that the phone screen was not visible and only recording then, but even then that recording would be imperfect, and somebody would have noticed. There is no way for the app to do what the author is describing.
I believe the battery drain would be an even better indicator. I'm sure if an app would constantly do audio processing in the background it would dramatically lower the battery life.
It would not need audio processing in real time; using voice oriented codecs realtime transmission is totally possible without any detectable impact on data throughput. Take a look at Codec2's required bandwidth compared to the fidelity it offers.
http://www.rowetel.com/?page_id=452
A couple weeks ago, a friend sent me a screenshot, via Whatsapp, of a dating app profile for a girl named "Bilar." The following day, Facebook showed me a friend suggestion for a girl named Bilar. I've never met anyone by that name. I could be wrong but my immediate conclusion is that Facebook recognizes text in Whatsapp-sent images and feeds it into the social network's friend suggestion engine.
Could your friend have friended Bilar on FB, causing you to have a mutual friend with her?
The girl who was suggested was not the same one with whom he had matched. It was a girl in Latin America.
The author says the conversation was "total random discussion" but that seems rather unlikely. I think we all know how uncommon randomness is.
This discussion about listening came up a few years ago but about Facebook, who owns Instagram.
If his friend or whoever he was talking about this product, most likely it's in their tracking cookies from them googling it. This is especially true since they are familiar with the product.
i wonder how often people think about and subsequently search the internet about consumer electronics after leisure hikes? i wonder what the top 5 consumer electronics items are in q3 2017.