Thinking out loud: In an attempt to vastly improve the data, could a mobile app be written that can "detect" if you are driving (exact location, speed, alignment/frequency to your past paths, etc), in such a way that the data could be automatically collected and crowdsourced?
Fire up the app, let it run in background, and it logs everything passively and adds it to global data set. Feasible?
Fire up the app, let it run in background, and it logs everything passively and adds it to global data set. Feasible?