oh three20 was an objective-c iphone library named 320 because that was the size of the screen. Created by facebook but everyone started using it until iphones started to come in other sizes!
I recall people dropping three20 long before screen sizes were an issue. I can't speak to all the issues with its design; I think I got to the part where it tried to model navigation similar to Ruby on Rails' routes and gave it a big "Nope."
