A smartphone is a mobile phone built on a mobile operating
system, with more advanced computing capability and connectivity
than a feature phone. The first smartphones combined the
functions of a personal digital assistant (PDA) with a mobile
phone. Later models added the functionality of portable media
players, low-end compact digital cameras, pocket video cameras,
and GPS navigation units to form one multi-use device. Many
modern smartphones also include high-resolution touchscreens and
web browsers that display standard web pages as well as mobile-
optimized sites. High-speed data access is provided by Wi-Fi and
mobile broadband. In recent years, the rapid development of
mobile app markets and of mobile commerce have been drivers of
smartphone adoption. The mobile operating systems (OS) used by
modern smartphones include Google's Android, Apple's iOS,
Nokia's Symbian, RIM's BlackBerry OS, Samsung's Bada,
Microsoft's Windows Phone, Hewlett-Packard's webOS, and embedded
Linux distributions such as Maemo and M