A:Answer Simpler to use.. For consistency, I try to weigh myself each day at the same time. The Wi-Fi enabled Aria makes it much simpler to hop on there, and be done, with the added benefit of getting a reading of your percentage of body fat (which also translates to BMI on the Fitbit site and app). I don't put 100% faith in the accuracy of the body fat percentage, but over time, you get an idea of how you are trending. I used to use the app to record my weight, but am more consistent with the Aria since it records it for me.