When I was in Ambulatory Care they did the stats and put the finger oxymeter on and scribbled it all down and went away. Sister pops back and asks if I have AF still? I said yes? Okay no problem I need to do a physical check of your pulse then for the full minute. It seems that when in AF it will calculate the heart rate based on the faster heart beats. This will also do it on the single ones the doctors and bought from Amazon etc. do.
So I could show 159 on the oxymeter but on the AF real time check I could be 130. The one I have does show each beat so I can usually see it going into free jazz mode. But I have seen the difference my self on my own so another fact I can add to my list of useless facts.