A smartphone is a mobile phone with an advanced mobile operating system which 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 cell phone, such as the ability to receive and make phone calls and text messages, with those of other popular digital mobile devices. Other features typically include a personal digital assistant (PDA) for making appointments in a calendar, media player, video games, GPS navigation unit, digital camera, and digital video camera. Most smartphones can access the Internet and can run a variety of third-party software components. They typically have a color graphical user interface screen that covers 70% or more of the front surface, with an LCD, OLED, AMOLED, LED, or similar screen; the screen is often a touchscreen.

In 1999, the Japanese firm NTT DoCoMo released the first smartphones to achieve mass adoption within a country. Smartphones became widespread in the 21st century and most of those produced from 2012 onwards have high-speed mobile broadband 4G LTE, motion sensors, and mobile payment features. In the third quarter of 2012, one billion smartphones were in use worldwide. Global smartphone sales surpassed the sales figures for regular cell phones in early 2013. As of 2013, 65% of U.S. mobile consumers own smartphones. By January 2016, smartphones held over 79% of the U.S. mobile market.