Ask HN: How to monetize for an extremely niche market?

I am currently near the end of creating an iOS application that focuses on making it easier for students at my University to check the bus timetable. The timetable is only available either at the bus stops, or online as a difficult to read PDF document. Most bus stops aren't even covered, but my application estimates them from distance and time measurements. Furthermore I've pinned down every bus stop on the route by parsing OpenStreetMap. These bus stops are not available anywhere else (and especially not with any times associated with them).

Some screenshots are available here: https://i.freeih.com/7278/iphone_screenshot.png https://i.freeih.com/7279/iphone_screenshot_3.png

How would you go about monetizing such an application, if at all possible? Obviously, it will never make much, but pocket money would be pretty awesome, no one has paid me for my apps before.

My ideas: - Fully free app with ads. The ads would come from reaching out to local student centric businesses (student lettings agencies, pubs, bars, clubs etc) and possibly including student offers via the app. - Free basic version with iOS ads, pro version without ads + added features such as reminders

I wish to pursue the first idea as it sounds interesting to go and talk to these businesses and see what they think. Any advice?