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Early years
Mobile rigs were predecessors of mobile phones, along with taxicab radios, two way radios in police cruisers and the like. A large community of mobile radio users, known as the mobileers, popularized the technology that would eventually give way to the mobile phone. Originally, mobile phones were permanently installed in vehicles, but later versions such as the so-called "bag phones" were equipped with a cigarette lighter plug so that they could also be carried, and thus could be used as either mobile or as portable phones.
What was possibly the first real mobile phone, in the sense that it was connected to the telephone network, was tested by the Swedish police in 1946 for use in police cruisers. Half a dozen calls could be made before the police car's battery ran out. Radiophones began to be publicly available in the US at the end of the 1940s, though the distinction between such phones and a two-way radio becomes blurry since special systems are required to "patch" into the phone network with the assistance of human operators. Recognizable mobile phones with direct dialing have existed at least since the 1950s. One of the first truly successful public commercial mobile phone networks was the Autoradiopuhelin (ARP) network in Finland, launched in 1971. Posthumously, ARP is sometimes viewed as a ''zeroth generation'' (0G) network, being slightly above previous proprietary and limited coverage networks. A '''mobile phone''' or '''cell phone''' is an electronic telecommunication device with the same basic capability as a conventional landline telephone, but which is also entirely portable and is not required to be connected with a wire to the (Public Switched Telephone Network). Most current mobile phones connect instead to the network using a wireless radio wave transmission (the exception is satellite phones). These mobile phones communicate via a cellular network of base stations (cell sites), which is in turn linked to the conventional telephone network. In the late 1970s and early 1980s the car phone was the only mobile phone available. In addition to the standard voice function of a telephone, a mobile phone can support many additional GSM services such as SMS (Short message service) for text messaging, packet switching for access to the Internet, and MMS (Multimedia Messaging Service) for sending and receiving photos and video. Some of the world's largest mobile phone manufacturers include Alcatel, Audiovox, and Fujitsu, Kyocera (formerly the handset division of Qualcomm, LG ( Korea), Motorola, NEC, Nokia, Panasonic (Matsushita Electric), Philips, SAGEM, Samsung, Sanyo, Sharp, Siemens AGSiemens, SK Teletech, Sony Ericsson, and Toshiba.
There is also specialist communication systems related to, but distinct from mobile phones, such as satellite phones and Professional Mobile Radio. Mobile phones are also distinct from cordless telephones, which generally operate only within a limited range of a specific base station.
Mobile phone features
Mobile phones often have features beyond sending text messages and make voice calls—including Internet browsing,music (MP3) playback, personal organizers, e-mail, built-in cameras and camcorders, ring tones, games, radio, PTT (Push-to-Talk), infrared and Bluetooth connectivity, call registers, and ability to watch streaming video or download video for later viewing.
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