Glucose monitoring would be great, no doubt it’s coming but haven’t seen one yet. 2 or 3 years ago I got a Fitbit that does ECG. You hold the watch on diagonally opposite corners for 30 seconds. It shows you a two-dimensional trace as your heart beats, like a medical ECG screen, but I don’t know if it’s meaningful. At the end of the 30 seconds you get one of two messages, to the effect of “You’re okay - nothing abnormal detected,” or “Something seems off - you should get checked by a doctor.”
It also analyzes your sleep, and it connects to an app on your phone. After sleeping, you bring the watch and phone close together so the phone can sync with the watch. You get a plot of your sleep from start to finish, and totals of REM, deep and light sleep, as well as episodes of wakefulness. The watch uses skin temperature, heart rate, arm motion, maybe more stuff to figure out what stage of sleep you’re in.
I never got any ‘bad’ ECG messages, but do really like the sleep reports.