i don't mean to be negative, but i'm not really seeing the usefulness of this app. the only useful feature i see is the automatic volume adjustment based on speed. other than that, why would you want to play music based on the direction you're travelling?
i was thinking it may be useful if you could set it up so it plays a certain playlist based on a route you are taking. for instance, if you are picking up a friend, it would automatically start playing music that he/she likes as soon as you leave the house. i don't know if this would be possible, since i'm not familiar with how accurate a gps system can get.
btw, do you know who the impossibles are? i happened to notice you're from their home town. they kick ***