BBC NEWS | Technology | Mobile phone technology turns 20The technology behind the mobile phone is celebrating its 20th anniversary. On 7 September 1987, 15 phone firms signed an agreement to build mobile networks based on the Global System for Mobile (GSM) Communications. According to the GSM Association there are more than 2.5 billion accounts that use this mobile phone technology. Adoption of the technology shows no signs of slowing down with many de
