How does eavesdropping on a user's smartphone work?

Question

Android

Case 1, literally today. I am talking with a friend about the need to buy some equipment, but there is not enough money. My phone is on the table next to me. After 20 (!) minutes, a call comes from the bank with a proposal to issue a loan.
PS I'm not looking for anything from a smartphone on the Internet, I use it as a dialer and a camera, basically. I am not interested in loans in principle and have never looked for information about them from any of my devices, incl. from computers.
Case 2. Recently. Another friend told me about making money on the Internet, and that you need money for everything, and even sometimes you have to invest, for example, in a crypt. And he was immediately (!) called and offered to invest.
Case 3. Narrated by a trustworthy person: "My son came to me and tells me about the pictures and videos of Pripyat that he found .. And then an advertisement for dosimeters pops up to me."
Well, I read different references to similar cases on the internet. What they listen to is already a fact, not an assumption. But how does it work? Who or what is listening and what needs to be cut out to avoid leaking information?

Answer 1

Sharp topic. I will give a link to a site in which something is written without technical details and with an emphasis on paranoids, there is not much, but at least some systemic description. If you are interested in the future, you can dig deeper
https://book.cyberyozh.com/en/kibershpionazh-chere...

Answer 2

coincidence. less phone numbers should shine left and right.

Answer 3

No one knows. So far, no one has even been able to convict mobile phones of listening.

Answer 4

There is such an effect when you think about something, you begin to notice that you come across it more often, in advertising, in life, etc. With a probability of 99%, this is exactly what you have - just coincidences to which the brain ascribes significance. Correlation does not imply causation.

Answer 5

Worked for a mobile operator. Monitored his mobile phone for a paranoid friend. A friend regularly told me that his mobile phone was listening to him, that Google showed him ads about recent conversations. He did not even install any applications and turned off everything "unnecessary". When I told him that for a couple of months the mobile had never transmitted anything suspicious anywhere, he did not believe me and told me about the "magic" data transmission past our networks. Then I brought him a radio electronics friend and we "listened" to the radio module of his mobile for an hour. Nothing but control sequences.

Answer 6

here is a link for you to think
https://lifter.com.ua/en/628

Answer 7

Coincidence, nothing more.