I have had the same type of issue on the sleep tracking as seems was on the original galaxy active. I wear a Fitbit which syncs exactly to my sleep times and has a nice graph showing the stages of sleep. It shows I usually get about an hour or a little more of Deep Sleep per night. It seems to make sense as you see it in the graph. The Active 2 is totally messed up on my sleep times, number one. I even manually put it on Goodnight Mode right before I settle down to sleep. It shows I get about 12-13 minutes of deep sleep. That makes me tired just looking at it.
The times were not correct as well as the stages, I believe. The Fitbit tracks by heart rate, the Active 2 by either heart rate or movement. I switched it to movement and I got a little over 5 hours of motionless sleep, which doesn't tell me too much.
The next issue is that I went to a Samsung rep that works in Best Buy location in my area who is helping me with my issues with the phone. He told me to make sure I close all my apps (need to be more diligent) and then automatically restart the phone for sometime like 3 am. We set it to that and it interrupted my sleep pattern in that it started tracking, and then around 3 am. it stopped and erased everything before it. It game me a message in the morning that I had to unlock my phone, which I did. Then it recorded about 20 minutes of sleep time. I don't get it. I guess I can't restart it during the sleep cycle.
There is also an issue with the Do Not Disturb in that if I sync it with my phone or not, I set it from 9 pm to 8 am and one day it woke me up at 6am, the other at 7 am and is staying at 7 instead of 8. Any clues how to fix this and/or the other sleep tracking issue? Seems like times are not correct.
I have the same issues with the deep sleep tracking. FitBit had me in the 1 hour to 2 hour range (normal for an average 8 hour sleep), and now my Samsung Galaxy Active 2 shows anywhere from 6 minutes to 32 minutes on the high end. I've never had an issue with it tracking my fall asleep and wake-up times, but the actual minutes per sleep stage seems a bit off.
Mine registers me as awake in the middle of the night for hours even though I'm sleeping. Goodnight Mode turns itself off I think during this time. Mine also shows much less deep sleep than what my Fitbit used to show.
The sleep tracking portion of the Active 2 needs big help. It should not see movements as awake times IMO. Shouldn't it be solely based on your heart rate or a combination of the two? I lay in bed for hours just googling on my phone and the Active 2 thinks I'm sleeping because I'm not moving...
Day 2 of my use of this watch & it showed me awake for an hour and a half in the middle of the night when I wasn't. This was just wildly wrong. Not OK, and undermines my confidence in everything else.
I don't think I ever expected perfectly accurate sleep tracking statistics but I was hoping for relatively consistent sleep tracking so I could use one day's statistics in comparison to another. It was working okay for the first week and I started a "journal" in Excel just to see if REM or deep went up or down etc. Last night though it showed that I only slept for about 4 hours (12:10am to 4:08am). I actually woke up around 6am and was quite refreshed and remembered vivid dreams before waking so I'm not sure what happened. Some of the issues seemed to begin when I started using the Do Not Disturb which I set for 11pm to 6am; Sunday through Friday. Has anyone experienced this?
I also found that when I first used Theatre mode instead of DND, it totally shut down sleep tracking. I set it for the maximum 4 hours so the watch wouldn't glow brightly for a while but it didn't show me starting to sleep until 3am which was 4 hours after I actually went to bed. They don't explain the differences between Theatre, DND and Good Night modes very well.
I have gotten detailed sleep tracking the first 6 nights with the Active2... but somehow last night it only tells me that I was asleep, with no breakdown of REM/Light/Deep. No settings were changed and watch was at 90% charged... hope this doesn't become a regular thing :/