mobile phone mobile phone a mobile phone (cellphone, etc.) 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, as opposed to a fixed-location phone (landline phone). 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 cellphones (or "cell phones") in north america. in addition to telephony, digital mobile phones support a variety of other services, such as text messaging, multimedia messaging, email, internet access (via lte, 5g nr or wi-fi), short-range wireless communications (infrared, bluetooth), satellite access (navigation, messaging connectivity), business applications, video games and digital photography. mobile phones offering only basic capabilities are known as feature phones; mobile phones which offer greatly advanced computing capabilities are referred to as smartphones. two decades of evolution of mobile phones, from a 1992 motorola 8900x-2 to the 2014 iphone 6 plus the first handheld mobile phone was demonstrated by martin cooper of motorola in new york city on 3 april 1973, using a handset weighing c. 2 kilograms (4.4 lbs). in 1979, nippon telegraph and telephone (ntt) launched the world's first cellular network in japan. 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; enough to provide one for every person on earth. in the first quarter of 2016, the top smartphone developers worldwide were samsung, apple and huawei; smartphone sales represented 78 percent of total mobile phone sales. for feature phones (slang: "dumbphones") as of 2016, the top-selling brands were samsung, nokia and alcatel. mobile phones are considered an important human invention as it has been one of the most widely used and sold pieces of consumer technology. the growth in popularity has been rapid in some places, for example in the uk the total number of mobile phones overtook the number of houses in 1999. today mobile phones are globally ubiquitous, and in almost half the world's countries, over 90% of the population own at least one. history martin cooper of motorola, shown here in a 2007 reenactment, made the first publicized handheld mobile phone call on a prototype dynatac model on 3 april 1973. a handheld mobile radio telephone service was envisioned in the early stages of radio engineering. in 1917, finnish inventor eric tigerstedt filed a patent for a "pocket-size folding telephone with a very thin carbon microphone". early predecessors of cellular phones included analog radio communications from ships and trains. the race to create truly portable telephone devices began after world war ii, with developments taking place in many countries. the advances in mobile telephony have been traced in successive "generations", starting with the early zeroth-generation (0g) services, such as bell system's mobile telephone service and its successor, the improved mobile telephone service. these 0g systems were not cellular, supported few simultaneous calls, and were very expensive. the motorola dynatac 8000x. in 1983, it became the first commercially available handheld cellular mobile phone. the first handheld cellular mobile phone was demonstrated by john f. mitchell and martin cooper of motorola in 1973, using a handset weighing 2 kilograms (4.4 lb). the first commercial automated cellular network (1g) analog was launched in japan by nippon telegraph and telephone in 1979. this was followed in 1981 by the simultaneous launch of the nordic mobile telephone (nmt) system in denmark, finland, norway, and sweden. several other countries then followed in the early to mid-1980s. these first-generation (1g) systems could support far more simultaneous calls but still used analog cellular technology. in 1983, the dynatac 8000x was the first commercially available handheld mobile phone. in 1991, the second-generation (2g) digital cellular technology was launched in finland by radiolinja on the gsm standard. this sparked competition in the sector as the new operators challenged the incumbent 1g network operators. the gsm standard is a european initiative expressed at the cept ("conférence européenne des postes et telecommunications", european postal and telecommunications conference). the franco-german r&d cooperation demonstrated the technical feasibility, and in 1987 a memorandum of understanding was signed between 13 european countries who agreed to launch a commercial service by 1991. the first version of the gsm (=2g) standard had 6,000 pages. the ieee and rse awarded to thomas haug and philippe dupuis the 2018 james clerk maxwell medal for their contributions to the first digital mobile telephone standard. in 2018, the gsm was used by over 5 billion people in over 220 countries. the gsm (2g) has evolved into 3g, 4g and 5g. the standardisation body for gsm started at the cept working group gsm (group special mobile) in 1982 under the umbrella of cept. in 1988, etsi was established and all cept standardization activities were transferred to etsi. working group gsm became technical committee gsm. in 1991, it became technical committee smg (special mobile group) when etsi tasked the committee with umts (3g). dupuis and haug during a gsm meeting in belgium, april 1992 personal handy-phone system mobiles and modems, 1997–2003 in 2001, the third generation (3g) was launched in japan by ntt docomo on the wcdma standard. this was followed by 3.5g, 3g+ or turbo 3g enhancements based on the high-speed packet access (hspa) family, allowing umts networks to have higher data transfer speeds and capacity. by 2009, it had become clear that, at some point, 3g networks would be overwhelmed by the growth of bandwidth-intensive applications, such as streaming media. consequently, the industry began looking to data-optimized fourth-generation technologies, with the promise of speed improvements up to ten-fold over existing 3g technologies. the first two commercially available technologies billed as 4g were the wimax standard, offered in north america by sprint, and the lte standard, first offered in scandinavia by teliasonera. 5g is a technology and term used in research papers and projects to denote the next major phase in mobile telecommunication standards beyond the 4g/imt-advanced standards. the term 5g is not officially used in any specification or official document yet made public by telecommunication companies or standardization bodies such as 3gpp, wimax forum or itu-r. new standards beyond 4g are currently being developed by standardization bodies, but they are at this time seen as under the 4g umbrella, not for a new mobile generation. types active mobile broadband subscriptions per 100 inhabitants. smartphone smartphones have a number of distinguishing features. the international telecommunication union measures those with internet connection, which it calls active mobile-broadband subscriptions (which includes tablets, etc.). in the developed world, smartphones have now overtaken the usage of earlier mobile systems. however, in the developing world, they account for around 50% of mobile telephony. feature phone feature phone is a term typically used as a retronym to describe mobile phones which are limited in capabilities in contrast to a modern smartphone. feature phones typically provide voice calling and text messaging functionality, in addition to basic multimedia and internet capabilities, and other services offered by the user's wireless service provider. a feature phone has additional functions over and above a basic mobile phone, which is only capable of voice calling and text messaging. feature phones and basic mobile phones tend to use a proprietary, custom-designed software and user interface. by contrast, smartphones generally use a mobile operating system that often shares common traits across devices. infrastructure cellular networks work by only reusing radio frequencies (in this example frequencies f1-f4) in non adjacent cells to avoid interference the critical advantage that modern cellular networks have over predecessor systems is the concept of frequency reuse allowing many simultaneous telephone conversations in a given service area. this allows efficient use of the limited radio spectrum allocated to mobile services, and lets thousands of subscribers converse at the same time within a given geographic area. former systems would cover a service area with one or two powerful base stations with a range of up to tens of kilometres (miles), using only a few sets of radio channels (frequencies). once these few channels were in use by customers, no further customers could be served until another user vacated a channel. it would be impractical to give every customer a unique channel since there would not be enough bandwidth allocated to the mobile service. as well, technical limitations such as antenna efficiency and receiver design limit the range of frequencies a customer unit could use. a cellular network mobile phone system gets its name from dividing the service area into many small cells, each with a base station with (for example) a useful range on the order of a kilometre (mile). these systems have dozens or hundreds of possible channels allocated to them. when a subscriber is using a given channel for a telephone connection, that frequency is unavailable for other customers in the local cell and in the adjacent cells. however, cells further away can re-use that channel without interference as the subscriber's handset is too far away to be detected. the transmitter power of each base station is coordinated to efficiently service its own cell, but not to interfere with the cells further away. automation embedded in the customer's handset and in the base stations control all phases of the call, from detecting the presence of a handset in a service area, temporary assignment of a channel to a handset making a call, interface with the land-line side of the network to connect to other subscribers, and collection of billing information for the service. the automation systems can control the "hand off" of a customer handset moving between one cell and another so that a call in progress continues without interruption, changing channels if required. in the earliest mobile phone systems by contrast, all control was done manually; the customer would search for an unoccupied channel and speak to a mobile operator to request connection of a call to a landline number or another mobile. at the termination of the call the mobile operator would manually record the billing information. mobile phones communicate with cell towers that are placed to give coverage across a telephone service area, which is divided up into 'cells'. each cell uses a different set of frequencies from neighboring cells, and will typically be covered by three towers placed at different locations. the cell towers are usually interconnected to each other and the phone network and the internet by wired connections. due to bandwidth limitations each cell will have a maximum number of cell phones it can handle at once. the cells are therefore sized depending on the expected usage density, and may be much smaller in cities. in that case much lower transmitter powers are used to avoid broadcasting beyond the cell. in order to handle the high traffic, multiple towers can be set up in the same area (using different frequencies). this can be done permanently or temporarily such as at special events or in disasters. cell phone companies will bring a truck with equipment to host the abnormally high traffic. capacity was further increased when phone companies implemented digital networks. with digital, one frequency can host multiple simultaneous calls. additionally, short-range wi-fi infrastructure is often used by smartphones as much as possible as it offloads traffic from cell networks on to local area networks. hardware the common components found on all mobile phones are: a central processing unit (cpu), the processor of phones. the cpu is a microprocessor fabricated on a metal–oxide–semiconductor (mos) integrated circuit (ic) chip. a battery, providing the power source for the phone functions. a modern handset typically uses a lithium-ion battery (lib), whereas older handsets used nickel–metal hydride (ni–mh) batteries. an input mechanism to allow the user to interact with the phone. these are a keypad for feature phones, and touch screens for most smartphones (typically with capacitive sensing). a display which echoes the user's typing, and displays text messages, contacts, and more. the display is typically either a liquid-crystal display (lcd) or organic light-emitting diode (oled) display. speakers for sound. subscriber identity module (sim) cards and removable user identity module (r-uim) cards. a hardware notification led on some phones low-end mobile phones are often referred to as feature phones and offer