BlackBerry OS is a proprietary mobile operating system for the BlackBerry line of smartphones, both developed by BlackBerry Limited (formerly Research In Motion). BlackBerry 10 is based on QNX, a Unix-like operating system that was originally developed by QNX Software Systems until the company was acquired by BlackBerry in April 2010. As a result of the acquisition, BlackBerry released BlackBerry Tablet OS for the BlackBerry PlayBook, large parts of which were subsumed by BlackBerry 10. It supports the application framework Qt (version 4.8) and features an Android runtime to run Android applications. Prior to version 10.3.1, BlackBerry 10 also supported the Adobe AIR runtime. The user interface uses a combination of gestures and touch-based interactions for navigation and control, making it possible to control a device without having to press any physical buttons, with the exception of the power button that switches the device on or off. It also supports hardware keyboards, including ones which support touch input.