Hi, you can travel with an mobile pass or paper pass. The paper pass can also be use hybrid with the pass as paper and to write every ride on the app. 

Hi @Raquel Almeida 

You can buy either a Paper Pass (not always available and you have to keep in mind the shipping time) or a Mobile One. Seat reservations (when required) are separated, so you would have to show these at the inspector of the train. 

Dear @Angelo, from January 2023, it is not going to be possible to fill your journeys on the App when having a Paper Pass. This is due to the complaints of some inspectors getting confused between the Passes. 

Have a lovely day you both!