Why do some android smart watches give two values for ppg (Photoplethysmography) at the same time?
I am collecting ppg from Fossil watches gen 4 and gen 5 each measurement gives two ppg measurements. I see they are related, when one drops so does the other but I don't know the difference between the two. I am having trouble finding documentation on this.
I tried googling this and found no clear documentation from wear OS, android or fossil. I'm sure it probably exists somewhere but I can not find it.
