Your phone isn't secretly listening to you, but the truth is more disturbing

People seem to ignore the cost and accuracy aspects of a phone listening to you 24/7. At least with today’s constraints, it is highly unlikely to be happening.

First, the cost to transcribe audio is not free. It is computationally expensive. Any ad network or at scale service would not be able to afford it, especially in orgs where they are concerned about unit economics.

Secondly, the accuracy would be horrible. Most of the time, your phone is in your pocket and would pick up almost nothing. More over, it’s not like you are talking about anything of value to advertisers in most cases. Google is a money printing machine because people search with an intent to buy. The SNR of normal conversation is much much much lower. That makes the unit economics of doing this gets much worse.

Third, it would be pretty hard to not notice this was happening. Your phone would get hot, your battery would deplete very quickly, and you’d be using a lot of data. Moreover on iOS you could see the mic is being used and the OS would likely kill the app if it was using too many resources in the background.

So until we find an example of this actually happening, it’s not worth worrying about.

For all of these reasons, audio snooping is much more likely to be something done by wired, stationary devices that maybe have a decent amount of RAM + a fair bit of usually-idle processing capacity (to run the transcription model locally and just push the resulting text), and which are expected to draw a decent amount of power and use the Internet at vaguely-arbitrary times.

Like a smart TV, for example.