Fantastic app to rapidly see the effects of variables such a road grade, wind speed, temperature, bike weight, rider weight, altitude, riding position, road surface, tire type, and transmission efficiency on speed and power (watts). The app requires some time to learn how to operate it (not instinctive). I think it is recommendable to go to the maker's website and familiarize yourself with the bike calculator's data points on one screen.
Pretty amazing application.