I used to have mine mounted on my handlebar as I used the Wahoo Fitness app as my bike computer. Once I switched to a Garmin Edge 500, that took its place on the bar. I still carry the phone on me -- in a SpiBelt hip belt that I also use for running -- for emergencies, as others have noted. I can always check Google Maps if I'm lost, or I can call my wife to bring the "team car" if my bike is disabled. Fortunately, neither emergency scenario has happened but I'm prepared regardless.