We’re still waiting for Tim Cook’s Apple Watch. On campus he wears a prototype which monitors his sugar levels (he’s diabetic). He has several times mentioned that in fireside chats/interviews. There’s also a FDA and FTC license for Apple but the monitor is not detailed, which means they probably think they’ve found the right size but not yet how to fit it in the Watch optimized for mass production.

But yeah it’s a hugely promising niche and with processors now being made at 5nm we can expect neural learning in watches soon as well.

I would only trust all that data to a company with an actual pro-privacy position like Apple though. Google has long time ago damaged any privacy trust I may have had.