I've found the UP bracelet useful since its faltering launch last year -- I never saw the recharging problems others have had. I was having issues synching it (it would take half a dozen tries before it would be recognized and synch) but a software update to the app corrected that.
When my mother was recovering from surgery, her sleep patterns were irregular and she was concerned that she wasn't sleeping well. I put my UP bracelet on her wrist and reassured her by showing the graphs of how often she woke, but how much sleep she was still getting and how much of it was deep sleep.
I now have one of the improved bands and it has worked well. The software added nutritional tracking that has enabled me to lose 30 pounds over a few months without really trying -- just being more conscious of which foods were really adding on the calories.
I've gotten a great deal of value from this and I encourage my friends and family to use it too.
My wife and I have been using if for more than 30 Days, it is interesting to see your sleep pattern and it has caused us to get more sleep and feel better in the following day. It fairly accurately measures steps but it is important to set your own step measurement to be accurate. You can also enter your food into the app each day. Interesting I discovered I fall asleep in 11 minutes almost every night, I can see my deep sleep time and light sleep time. My wife discovered she wakes up several times during the night. It is helping us to change our patterns to be more healthy.