A:AnswerI don't think it does I have not used it for sleep I wear a cpap mask and have had sleep studies testing my oxygen level at night so I don't need that function
A:AnswerNo gps. Never used it but I believe it can use your phones gps to do certain functions. Yea on daylight saving. I believe a lot of this is done based on your phone.
A:AnswerIf your Fitbit is waterproof, then you're fine to wear it for water aerobics or while taking a shower etc. If it's not. Don't do it. You will mess it up. The wife and I just returned ours for upgrade and found out they do not offer warranties anymore. This sucks! As we did have a few issues with a couple not charging and was able to exchange. Now, we would have to buy another if a serious problem happened. But for the most part, the Fitbit's last long... in my experience.
A:AnswerNO. All fitbit trackers suspend HR monitoring in the water. This is due to refraction messing up the readings. It has been suggested that the only way to get this to work is to have a chest band which of course the Charge 3 does not have.