Hi. I work at Fitbit. I don't speak for Fitbit, but the page below does. You are probably right that real time sleep phase data would require EEG, but wrong abo

Hi. I work at Fitbit. I don't speak for Fitbit, but the page below does. You are probably right that real time sleep phase data would require EEG, but wrong about Fitbit using motion data to infer sleep phases. Without heart rate Fitbit only measures awake/restless/asleep. REM/deep/light is estimated only when heart rate data is available. https://help.fitbit.com/articles/en_US/Help_article/2163#AutomaticDetection https://help.fitbit.com/articles/en_US/Help_article/2163#Aut...