A smartphone is a mobile phone (also known as cell phones or cell mobiles) with an advanced mobile operating system that combines features of a personal computer operating system with other features useful for mobile or handheld use. Smartphones, which are usually pocket-sized, typically combine the features of a mobile phone, such as the abilities to place and receive voice calls and create and receive text messages, with those of other popular digital mobile devices like personal digital assistants (PDAs), such as an event calendar, media player, video games, GPS navigation, digital camera and digital video camera. Smartphones can access the Internet and can run a variety of third-party software components ("apps"). They typically have a color display with a graphical user interface that covers more than 76% of the front surface. The display is almost always a touchscreen, which enables the user to use a virtual keyboard to type words and numbers and press onscreen icons to activate "app" features.