A mobile phone, known as a cell phone in North America, is a portable telephone that can make and receive calls over a radio frequency link while the user is moving within a telephone service area. The radio frequency link establishes a connection to the switching systems of a mobile phone operator, which provides access to the public switched telephone network (PSTN). Modern mobile telephone services use a cellular network architecture, and, therefore, mobile telephones are called cellular telephones or cell phones, in North America. In addition to telephony, 2000s-era mobile phones support a variety of other services, such as text messaging, MMS, email, Internet access, short-range wireless communications (infrared, Bluetooth), business applications, video games, and digital photography. Mobile phones offering only those capabilities are known as feature phones; mobile phones which offer greatly advanced computing capabilities are referred to as smartphones.The first handheld mobile phone was demonstrated by John F.
Mitchell12 and Martin Cooper of Motorola in 1973, using a handset weighing c. 2 kilograms (4.4 lbs).3 In 1979, Nippon Telegraph and Telephone (NTT) launched the world’s first cellular network in Japan.4 In 1983, the DynaTAC 8000x was the first commercially available handheld mobile phone. From 1983 to 2014, worldwide mobile phone subscriptions grew to over seven billion, penetrating virtually 100% of the global population and reaching even the bottom of the economic pyramid.5 In first quarter of 2016, the top smartphone developers worldwide were Samsung, Apple, and Huawei (and “smartphone sales represented 78 percent of total mobile phone sales”).6 For feature phones (or “dumbphones”) as of 2016, the largest were Samsung, Nokia, and Alcatel.7