I made this app for my own use and thought I would upload it to the app store as a free download in case anyone else needs this type of thing.
What does the app do? You set a minimum and maximum volume. Your device will be set to the minimum volume when standing still and as you start moving, the faster you are going the higher the devices volume will go.
This is good if you drive your car with your windows down or if you just have a car that is not good at keeping out the noise of the road when traveling on the highway.