Cue the Scroll PhoneTM.
I can’t even imagine the nightmare UI that would accommodate that type of screen.
Mechanically, I could see a device that has a slide down keyboard and a roll up screen. Functionally, I can’t see how it would be useful for daily smart phone actions like one-handed use or swipe-gestures.
This has to have been some form of egregious waste.
I can’t recall seeing any promotional material for this besides the trailer being reposted to talk shit about the movie.