I discovered that there is a new type of screen for printing, but I cannot make it print multiple pages (such as large tables that should span over several pages). The (undocumented) Print() function is basically just a shortcut for CTRL+P.
I noticed that Print() function and those new screens too. I tested it quickly with a sharepoint list form, which was a long scrollable form, and it printed only the the part that was visible on the screen. So it wasn't working like I was hoping.. or maybe I just didn't get it 🙂
I also noticed that printing only worked in the studio and not after publishin my app. I looked at the browser dev tools console and there was an error: "Ignored call to 'print()'. The document is sandboxed, and the 'allow-modals' keyword is not set." I haven't tested with standalone apps yet.