Velcro! I use Velcro in all my vehicles and motorcycle. Works great on rental cars to! My preferred location for a smart phone is right in the middle of the steering wheel. My phone has a loop side strip on the back and hook side strips are attached anywhere you need them; Bedpost, toolbox, office desk, triple clamp, etc. Easy peazy. Hands free headgear sweeten the deal! And technically, even if you are touching it your hands are still on the steering wheel
