Cool app, but would need some more features to be actually useful. Here's my wishlist:
(1) Show line number next to buses and trams. (2) Option to disable auto-centering to GPS location (to demo the app to someone while in suburbs). (3) Line selection, show only specific line. (4) Draw the route of selected line to the map. (5) Quick button to open reittiopas.fi in browser with current location pre-filled. (6) More bus lines (but I guess that's not up to you).