The batteries run out very quickly!!! It requires 3 small round batteries to operate, which in this particular device run out very quickly. I would measure once a day and by the end of the week, it needed new ones.
If this battery issue was solved, I would give it 5 stars. The app that transfers the measurements and the screen brightness are positives, although I had the brightness turned off to make the batteries last longer and they still ran out.
Perhaps they should have designed it to work with AAA batteries.