Idea

This is how I would like my app to work. I think it's pretty easy to follow based on other apps I've used.

 Clicking next to 'Building' will open a drop down menu with all of the buildings at the Kelburn campus (CO, HM, MC, VZ etc) and likewise clicking next to 'Room' will open a drop down menu with the room numbers.

Once you enter your location these steps come up.

When you click the check box by one of the steps it puts a tick there and opens the next step.
There is an arrow on the side that you can click to change to the map system.

 The map will show the path to the destination as well as all of the checkpoints. The that you have ticked off will be in a highlighted colour. Your current location will appear as a red dot. From the map there is also an arrow on the side that can take you back to the checkpoint system.
I haven't put it into all of the pictures, but I would also have a top bar of icons with tasks that you might want to do at any point during the navigation. Like 'Home' which would take you back to the startup page. 'New Path' that lets you enter a new destination. 'Where am I?' recalculates your position, tells you the nearest landmark to where you are and gives you the list of checkpoints from your position to your destination. I think this would be helpful if you decide to take a detour while your en route. Also 'Exit' which takes you out of the app completely.