Maybe the S Health app has changed over time or is different depending on the phone. But, why do some show deep sleep or REM and some show as motionless? Fitbit generally shows more information, but is not compatible. I know this isn't exact science since you're wearing a watch and not a bunch of electrodes stuck to your body. I guess I was just hoping for a little more.
I think I'll test out some of the apps in the play stick store and see what I can find. I didn't buy the watch for this purpose. But, this function does intrigue me.
