A:AnswerIt does sink with my fitness pal which is a free app. It also shows the calories you are burning. So putting your food in my fitness pal and seeing the calories you are burning does give a good account
A:AnswerThere are several differences between the vivofit 2 and 3, but the first main difference would be the size of the screen. The vivofit 3 has a smaller screen, but it does have a much higher screen resolution. -JFH