According to Mac Rumors, a recently filed Apple patent shows that the future iOS devices, such as the iPhone 5, may feature illuminated controls similar to the second generation iPod. The article explains how the new design may feature a newly designed bezel around the main display with "controller buttons that glow and morph for work and play." It continues by explaining how "a secondary display could include multiple regions, and one or more of the regions could include multiple segments."
The second display on the device, made from "printed segmented electroluminescence", could be used for numerous applications, including being "selectively illuminated to provide one or more indicators that represented where or how a user can provide inputs to the device," the patent says. This new display could show extra controls for games or special applications and allow developers to control any icons shown without the need to interrupt the content being shown on the main display.
According to Patently Apple, the next generation device design will "incorporate various sensors including motion, positioning and physiological so as to understand the orientation of the display so it could change the secondary display orientation and illuminated buttons or indicators." This news follows a recently published article by Patently showing how the new bezel may not have a traditional home button, "Apple really spells out how the smart bezel may not require a Home Button and added controls like volume will simply require a swipe of your finger."