In 1999, the Japanese firm NTT DoCoMo released the first smartphones to achieve mass adoption within a country. Smartphones became widespread in the 21st century and most of those produced from 2012 onwards have high-speed mobile broadband 4G LTE, motion sensors, and mobile payment features. In the third quarter of 2012, one billion smartphones were in use worldwide. Global smartphone sales surpassed the sales figures for regular cell phones in early 2013. As of 2013, 65% of U.S. mobile consumers own smartphones. By January 2016, smartphones held over 79% of the U.S. mobile market.

Devices that combined telephony and computing were first conceptualized by Nikola Tesla in 1909 and Theodore Paraskevakos in 1971 and patented in 1974, and were offered for sale beginning in 1993. Paraskevakos was the first to introduce the concepts of intelligence, data processing and visual display screens into telephones. In 1971, while he was working with Boeing in Huntsville, Alabama, Paraskevakos demonstrated a transmitter and receiver that provided additional ways to communicate with remote equipment, however it did not yet have general purpose PDA applications in a wireless device typical of smartphones. They were installed at Peoples’ Telephone Company in Leesburg, Alabama and were demonstrated to several telephone companies. The original and historic working models are still in the possession of Paraskevakos.