Show HN: My first app, Taxonomy: your taxi traveling companion. Feedback wanted

This is my first app, it's a taxi "assistant" for want of a better term- gives you street intersections for bars and restaurants, tracks your journey and lets you share it with your friends, splits the cost between passengers and lets you bill each other using Venmo. The web site is:

http://www.taxono.my

and I have an introductory blog post about it's transition from hackathon entry to app at:

http://blog.untogether.co.uk/post/17301824816/introducing-taxonomy

It's NYC-only for now because it's entered into an NYC app competition (more on that below), and had to be done to a deadline so I haven't had a huge opportunity to get opinions- any and all feedback is welcomed! I intend to follow up with more blog posts about the tech backend of the app very soon, but it's 95% HTML5 in the app, and node.js on the remote server.

Shameless plug alert: It's entered into a City-run competition called NYC BigApps, and there is a public choice award. I'm way behind on votes, so if you like the app, I'd really appreciate a vote: http://bit.ly/yURqU8

Thanks!