For this specific idea, the battery is irrelevant as you have ready access to a car charger. CommuteTrack[1] is the app I found. It's listed for $5.00 but I h

For this specific idea, the battery is irrelevant as you have ready access to a car charger. CommuteTrack[1] is the app I found. It's listed for $5.00 but I haven't purchased it so I can't comment on the quality or functionality. [1] http://frequal.com/CommuteTrack/index.html http://frequal.com/CommuteTrack/index.html