Data can be transferred using ultrasonic frequencies,

Legit Uses -

Google Tone Google Tez

Bad Thing -

It has been used in the past for malicious activity by governments (if you know, you know).

I can be used to track people, like people’s devices screaming their ID and devices receiving other devices IDs.

Imagine a mall with ultrasonic beacons, and for iOS and Google Play Services, hear that.

Reports -

https://techcrunch.com/2018/01/02/some-apps-were-listening-to-you-through-the-smartphones-mic-says-report/

https://thehackernews.com/2017/05/ultrasonic-tracking-signals-apps.html

https://www.youtube.com/watch?v=1n_8zDIFmQU

Solution ?

How to stop my devices like browsers, Windows PC, macOS, Android, and Android apps, from sending and receiving these frequencies

THis is a dead Chrome extension - https://github.com/ubeacsec/Silverdog