The phone is a device that transmits voice signals. Its basic components include a power source, switch hook, dialer and ringer, transmitter and receiver, and anti-sidetone circuit. Advancements in electronics have also made it possible for phones to have “smart” features such as call-number identification and visual data display. This article will explain the basic construction of a phone, as well as the evolution of the device.

Phones contain a central processing unit (CPU), which is fabricated on a MOS integrated circuit chip. They typically use a lithium-ion battery, whereas older handsets used a nickel-metal hydride battery. In addition, handsets contain input mechanisms, which enable the user to input data. A feature phone typically has a keypad, while a touchscreen uses capacitive sensing.

Modern smartphones can support hundreds of different applications. These mobile applications, or “apps”, are designed to add features to smartphones. These applications are made available through centralized application stores. These stores allow users to purchase diverse apps and synchronize them across their devices. Many smartphone users are able to use multiple email accounts at once.

The first commercially available handheld mobile phone was the DynaTAC 8000x. It was launched on 3 April 1973. The handset was designed by Martin Cooper, a computer scientist at the University of California. It was also the first handheld mobile phone in the world.