A wall-mounted beginning
The telephone of the late nineteenth century was tied to a place. A box on the wall or a candlestick-shaped stand on a desk was connected by wire to an exchange. If you wanted to call someone, you went to the telephone. The history from that point to a smartphone in a pocket is the history of removing, one at a time, the constraints of that wire.
Cordless: freeing the handset
The first step was a short one. A cordless telephone has a base unit connected to the telephone line and a handset that communicates with the base by radio. Cordless phones became popular in the 1980s. Early models had a range of only a few hundred feet and were prone to interference and eavesdropping, since the signals were not protected. Later versions used higher frequencies, digital transmission and encryption, which improved range, sound quality and privacy.
A cordless phone moves within a house or yard, but it still depends on a fixed line and a base unit. The phone number belongs to the place, not to the person.
Mobile service before cellular
Radiotelephone service for vehicles appeared earlier than cordless phones. In 1946 a commercial mobile telephone service opened in St. Louis, Missouri, and other cities followed. Early systems relied on a single powerful transmitter covering a large area. Because a few channels were shared among many users, capacity was tiny, and a user often had to wait for a free channel. The equipment filled a car trunk and cost a lot.
The solution to the capacity problem was the cellular idea, worked out at Bell Laboratories in the late 1940s: divide the service area into small cells, each with its own low-power transmitter, and reuse the same frequencies in cells far enough apart not to interfere. As a user moves from one cell to another, the call is handed over. This concept was impractical until computers could manage the handovers, which arrived in the 1970s, and it is the foundation of all modern cellular networks.
The first handhelds
On April 3, 1973, Martin Cooper of Motorola made a call on a prototype handheld cellular phone, a landmark often cited as the first handheld mobile call in public. The commercial version, the Motorola DynaTAC, was approved in the United States in 1983 and went on sale the following year. It weighed about two pounds, had a battery that gave a short talk time, and cost nearly four thousand dollars. It was the first mobile phone that many people had seen, and the idea of a telephone for a person rather than a place was now real.
The first commercial cellular network had begun operating in Tokyo in 1979, and the first in the United States began in Chicago in 1983. These were analog systems. In the early 1990s, digital second-generation networks, including GSM, improved sound, capacity and security, and made text messages (SMS) standard.
Phones that did more than call
As phones became smaller and batteries better, particularly with the arrival of lithium-ion batteries, manufacturers began adding functions. Early digital phones included address books, games and alarm clocks. A device often counted as the first smartphone was the IBM Simon, shown in 1992 and sold in 1994. It combined a cellular phone with a calendar, an address book, email and fax capability, and a touchscreen that could be operated with a stylus. It sold in small numbers and had a short battery life, but it outlined what would follow.
In the following years, personal digital assistants and pagers merged with phones. Email-focused devices became popular with business users around 2000. Camera phones appeared in the early 2000s, and they changed photography habits as they spread. Third-generation networks allowed faster data, and early web access on phones was often clumsy.
The touchscreen smartphone
In 2007, Apple introduced the iPhone, with a large multi-touch screen, a full web browser and no physical keyboard. In 2008 phones using Google’s Android operating system appeared, and application stores let people download software from independent developers. The combination of touchscreen interfaces, fast data networks, GPS receivers, cameras and an app marketplace made the smartphone into a general-purpose pocket computer. Making calls became one of many functions, and for many users not the most frequent.
The shift is sometimes described as a mobile revolution because it affected so many activities: navigation, photography, banking, shopping, news and entertainment. Behind the screen, the phone still performs the basic job Bell’s device did, turning a voice into a signal and back into a voice.
What stayed and what changed
Some things remained constant. The telephone number is still an identifier, calls are still set up through switches (now mostly software), and the voice call is still a core service. Other things changed fundamentally: the handset became a personal device, the network became an international system of radio cells, and voice became one kind of data among many. Voice calls today often travel as internet packets for part of their journey, so the technical line from Bell’s wire to the smartphone is real but not straight.