Yes, and people hate them, but there are no alternatives. Why would you want something permanently in your ear to measure heart rate?

You want something in your ears for a majority of the time because they play music and drown out background noise. Gathering health data is just a good secondary benefit.

yeah ok. please never be in power I do not want to live in the matrix. I suppose if apple were developing something to plug in one's anus to measure the quality of fart air and microbiomes you'd buy-in. What a world we living in