This is my second or third FitBit device, and the least accurate and most frustrating to use. I consistently run into these issues: 1) device screen blacks out; requires factory reset to resolve, but then happens again. 2) steps counts that are far too high. I took my device off the charger yesterday morning, and it said I had walked 326 steps...all while the device was charging. 3) Device does not recognize physical activity. I will completed an exercise class (30-60 minutes long), then check later in the day to see that the activity was not tracked. Then when I manually add the activity, the device suddenly recognizes the activity from hours ago and now the results are doubled. 4) Now the device is carrying yesterday's steps into today. I completed 14000 steps by bedtime last night, at 2AM device registered 16000 steps and now it registers 18000 (I've been out of bed for an hour and done less than 500 steps). I did not experience these issues with other devices. I've followed the steps listed in other posts, but should not need to factory reset my device on a daily basis and should not need to trick the device, since prior devices worked more accurately. I am unlikely to buy a FitBit again.
