I bought the watch for its supposed characteristics in measuring my sleep. It seems to be able to distinguish between deep sleep and light sleep but It does not measure all the times that I was awake in the night even missing time when I actually got up. Last night I got up 4 times and the app showed 2. I woke up over a dozen times for short periods of 10 to 15 minutes and the watch did not collect this information. As the main reason for purchase was related to sleep and waking, for me, the watch was useless. Maybe, software updates will improve this. Obviously the sensors or algorithms are not programmed for this. Apart from this a good watch.