Something I made and open sourced 10 days ago. Quite similar to this, except, very few on HN bothered to take a look.
It's not very clear what to do when you land on the page and there's nothing to explain what it does. I wasn't sure what I had to put in for the start and end location. Is just a city name ok? or does it need a full address?
I'd suggest having an example location already selected. That way instead of asking the user to do something they can simply click the play button and immediately see what the app does.
Seems another idea's time has come.