The mobile networks at the times were abysmally slow and unreliable, the API I was using was slow, basically loading times were unacceptable, I needed the info without delay. No, actually pre-fetched even so that it was working even when offline. I ended up scheduling my app using Tasker so that when I was likely commuting it started updating the timetable in the background. Now I always had instant info available, as good as I could at least.
Plan was to release the app but I eventually realized I would never polish the app to a releasable state, but it still worked 100% for my exact usecase. So I never did get further than a beta test on the Play Store.