You are so right. Earlier this year I had to spend a week in hospital and they took a variety of measurements every day. It was interesting to see how much variation there was, especially in blood pressure. But one thing was especially interesting, pulse. As I was wearing my Apple watch, I had the values for blood and blood oxygene before they took them. And with pulse, you could clearly see with the graph, how much systematic variation there was. So their single measurement was not great. Best example, the last measurement was taken before I was about to be released, awaiting the doctors sign-off visit. Of course my pulse was off. But the doctor was quite interested to see my pulse for the last couple of hours.

People underestimate how valuable a medical tool the Apple watch already is and how game-changing it can get if they manage to extend the sensor suite - as you say, blood pressure, perhaps also body temperature and glucose level.

Another fun fact from the visit, they did monitor glucose level and one morning they did so directly after waking me up. Which caused the nurse to run to get me an early breakfast as it was very low. Not as if I hadn't known for decades, that I need a slow start and at least a small bite for breakfast to get into gears...