No PDF, you have to show it on your phone. But you don’t need a data connection to show the ticket - it will work offline. (Just make sure you connect to wifi every couple of days or so to refresh the app.)

I’d also strongly recommend a local SIM - the ability to look up maps, directions, train schedules when things go wrong etc is invaluable.

The mobile pass needs a data connection:

1. To activate the pass (just once).
2. To activate a travel day (also on a continuous pass).
3. To generate the QR code by tapping on "Show ticket” for the first time (you should do that right after activating a travel day).
4. At least once every 72 hours.

After you've activated a travel day and generated the QR code for that day, you don't need internet anymore for that day. If it takes too long to show the QR code after that, then turn on flight mode.