Probably, but making it an app allows users to pre-download the whole thing beforehand so they don’t need to depend on cell data when they’re out in a field.
but I… it… it’s a PDF, its stored on my phone. I downloaded it. I actually still have it, if I need to prove I was on the train. its not in the app anymore, but I still have it here.
you know you can’t make a PURCHASE on an app without network access, right? like, it has to interact with your bank and generate the code (and that’s done on their server, so you can’t make yourself free tickets) and update “this ticket is valid” in the system. the app is literally just a web site with fewer features. all the important math happens on the server. usually, not even a timetable is stored locally, and it still has to be retrieved from the network, it doesn’t even cache, I bet. I could check, but I would have to find my phone.