The idea that your phone's microphone isn't constantly parsing speech into text and then occasionally uploading certain keywords to whichever major advertising platform (FB, Google, Amazon, etc) has an active app on the phone doesn't seem so far fetched. We know Android and Apple phones are generally always listening for their keyword phrase (Siri, Hey Google, etc) for voice-based AI assistants and that their speech-to-text support is very robust. Uploading a text log is very data efficient and becomes even more efficient if it merely sends a positive for certain keywords it's told to listen for based on the individual's demographic profile and advertiser's interest in said demographics. I've had enough "coincidences" happen to believe this can be explained otherwise.

We know for a fact that some phones are secretly listening and uploading stuff.[1-4] It's done by spying apps. How do we know? Because there are tons of researchers reverse engineering stuff trying to find this stuff. These researchers are extremely hungry for a big find, for some big publicity. They're searching very hard to find a big player doing it, but none of the big players are doing it, so they only make small headlines with the small players they find.

[1] https://www.zdnet.com/article/hundreds-of-apps-are-using-ult...

[2] http://christian.wressnegger.info/content/projects/sidechann...

[3] https://www.nytimes.com/2017/12/28/business/media/alphonso-a...

[4] https://web.archive.org/web/20190309034942/https://recon.med...