I decided to build an iOS app for my University's bus service that runs through the various campuses.
It was an interesting challenge as I had nothing but the printed timetables (http://www.nottingham.ac.uk/about/documents/903-times.pdf) to use as the data.
Thus I had to come with a suitable data structure that would complement the design & user experience i had in mind for the app.
I also decided to take the challenge of writing the app in swift. This project has helped me get to up speed with swift really quickly.