Talk:HRV (Heart Rate Variability)
Combine this with heart rate because this page is just about the devices that are better at HR. Maybe topic: HR and HRV and tools: tools for HR and HRV
potential source dump
https://old.reddit.com/r/WearOS/comments/qk2uj3/watches_for_heartrate_variability_sensing_and/ https://www.reddit.com/r/AcademicPsychology/comments/q91zfe/heart_rate_variability_biofeedback_improves/ https://www.reddit.com/r/CPTSD/comments/pytxlf/i_recently_learned_about_hrv_heart_rate/