Download LINK DEVOUR V3.2.3 OnLine
Italo and Trenitalia are the main train companies. They both have robust apps for finding train times and purchasing tickets, plus you can pay with a credit card or with PayPal before downloading your tickets to your smartphone immediately after purchasing. Alternatively, you can purchase your tickets online ahead of time and print them out. Or download and save the PDF you receive in the confirmation email.
Download DEVOUR v3.2.3 OnLine