Apple is likely next year will set the touch OLED screens on their flagship phones. This new generation of OLED displays, which will be slightly thinner than previous screens of this type.
A new generation of OLED-based screens are not touch the shell, and on special sensors located on the panel. Due to this, the displays become thinner, because there is no need to cover the entire screen of the touch layer. This technique is a bit cheaper and more efficient. At the moment, Apple uses the traditional screens, but this will change in the near future.