The Bike Stem Tool app is designed for cycling recreationists and enthusiasts who are interested in potentially swapping the stem for a better bike fit. With only a few straight-forward measurements, this app will determine the sitting position to handlebar reach and drop angle simply by swapping only the manufacturers' specifications of stems. Save both money from otherwise having to acquire a pile of stems, and save time from having to install potentially unwanted stems. With this app, the cyclist can compare the change in reach and drop amongst stems to more easily find the perfect one for a better bike fit.