Researchers from Queen's University Human Media Lab developed a prototype flexible OLED smartphone that uses active haptic feedback - or bend input - to control the device. As you can see in the video below, you can play games or flip through comic books by bending the device.
The prototype device use a 6" 720p Flexible OLED display produced by LG Display - that's the same kind of display that was used in LG's G Flex phone in 2013. The device runs Android 4.4 and includes haptic feedback motors and bend sensors.
This is just a prototype, of course, and the researchers will demonstrate it soon at the Conference on Tangible Embedded and Embodied Interaction in Eindhoven, Holland.
This is actually not a new concept. Back in 2011 (!) Nokia demonstrated a similar concept called the Kinetic, and in 2015 AUO demonstrated a bendable 5" 720p (295 PPI) AMOLED display that includes a film-type touch sensor.