Smartphone

Smartphones are a class of mobile phones and of multi-purpose mobile computing devices. They are distinguished from feature phones by their stronger hardware capabilities and extensive mobile operating systems, which facilitate wider software, internet (including web browsing over mobile broadband), and multimedia functionality (including music, video, cameras, and gaming), alongside core phone functions such as voice calls and text messaging. Smartphones typically include various sensors that can be leveraged by their software, such as a magnetometer, proximity sensors, barometer, gyroscope and accelerometer, and support wireless communications protocols such as Bluetooth, Wi-Fi, and satellite navigation.

Early smartphones were marketed primarily towards the enterprise market, attempting to bridge the functionality of standalone personal digital assistant (PDA) devices with support for cellular telephony, but were limited by their bulky form, short battery life, and the immaturity of wireless data services; these issues were eventually resolved with advances in MOSFET (MOS transistor), lithium-ion battery and mobile network technologies. In the 2000s, NTT DoCoMo's i-mode platform, BlackBerry, Nokia's Symbian platform, and Windows Mobile began to gain market traction, with models often featuring QWERTY keyboards or resistive touchscreen input, and emphasizing access to push email and wireless internet. Since the unveiling of the iPhone in 2007, the majority of smartphones have featured thin, slate-like form factors, with large, capacitive screens with support for multi-touch gestures rather than physical keyboards, and offer the ability for users to download or purchase additional applications from a centralized store, and use cloud storage and synchronization, virtual assistants, as well as mobile payment services.

Improved hardware and faster wireless communication (due to standards such as LTE) have bolstered the growth of the smartphone industry. In the third quarter of 2012, one billion smartphones were in use worldwide. Global smartphone sales surpassed the sales figures for feature phones in early 2013.

Background
The development of the smartphone was enabled by advances in MOSFET (metal-oxide-silicon field-effect transistor) semiconductor device fabrication. The MOSFET (MOS transistor), invented by Mohamed Atalla and Dawon Kahng at Bell Labs in 1959, is the basic building block of computing devices such as smartphones. MOSFET scaling, where MOS transistors get smaller with decreasing power consumption, enabled very large-scale integration (VLSI) technology, with MOS transistor counts in integrated circuit chips increasing at an exponential pace, as predicted by Moore's law. Continuous MOSFET scaling eventually made it possible to build portable smart devices such as smartphones during the 1990s–2000s. A typical smartphone is built from billions of tiny MOSFETs as of 2019, used in integrated circuits such as microprocessors and memory chips, as power devices, and as thin-film transistors (TFTs) in mobile displays.

Advances in MOSFET power electronic technology also enabled the development of digital wireless mobile networks, which are essential to the smartphone. The wide adoption of power MOSFET, LDMOS (lateral diffused MOS) and RF CMOS (radio frequency CMOS) devices led to the development and proliferation of digital wireless mobile networks in the 1990s, with further advances in MOSFET technology leading to increasing bandwidth during the 2000s. Most of the essential elements of wireless mobile networks are built from MOSFETs, including the mobile transceivers, base station modules, routers, RF power amplifiers, telecommunication circuits, RF circuits, and radio transceivers, in networks such as 2G, 3G, and 4G.