While the ZenBooks have a second touchscreen that's the size and in the location of a typical large touchpad, the Pro Duo's is expanded to the width of the laptop. The virtual number pad to the right of the keyboard now doubles as the touchpad.
The Ergolift hinge now angles to 7 degrees, the steepest angle Asus has implemented in one of its laptops. The design improves airflow for cooling and also serves to tilt the second screen to a better viewing angle.
Asus is also updating the Flip 15, replacing the standard touchpad with the second generation of its ScreenPad, Asus' small screen version of the ScreenPad Plus that initially debuted in the ZenBook Pro. The ScreenPad 2.0 is a little bigger than before, and much wider than the original touchpad in the Flip 15.
The updated version of the ScreenPad is more streamlined to use than the original version -- the custom apps are laid in a familar array, like a phone screen, for one, and Asus has made it quicker to toggle between ScreenPad and touchpad modes. Asus says it also consumes a lot less power now.