Apple Watch
 

I do not own on of these ...yet ;) but I just wanted to see if anyone else does.

It appears to have a spot on heart rate monitor even though it only tracks on the wrist. One was measured against our super sensitive pulse rate monitor we use for biofeedback and it was identical.

Anyone know what other capabilities it has to track things?

I just got one about a month ago. I use it to track my exercises (time & calories), my move calories burned, my standing up everyday. It syncs to my phone where I can view in more detail my steps for the day and daily overview. I also use it for the heart rate monitor. I haven't had a chance to explore more, other than what I've listed above. All my fashion statement watches have since been retired.