I have a serious issue with my fitbit charge 4 and it's accuracy in measuring my heart rate. I do a lot of cycling and I'll say that usually the HR monitoring seems good when outdoors, but when I do an indoor session the HR monitoring is terrible. It will not track my HR correctly at all; there I am panting away and my charge 4 says my HR is about 80bpm, then suddenly it drops even further and then suddenly rises again, all during a constant level of effort.
I've tried adjusting the position on my wrist, does nothing. I've tried the reset (as recommended in previous articles here) and that works for all of 10 seconds and then sometimes not at all. I've cleaned the charge 4 and my wrist and still no change....
I've rebooted it and this doesn't work and I'd really like to do a full on Factory reset it see if that works or reinstall the OS, but there doesn't seem to be a way to do this.
I sometimes wonder if I've just got a duff one......
This has made me wonder about the accuracy for everything else and shaken my trust in fitbits products.
I'd considered the charge 5, but having read the reviews and that there's a serious issue with having GPS and accurate heart rate monitoring.
