GSM is 20 years old

Wireless connection standard "Global System for Mobile Communications“ (GSM) this year on July 1st has reached 20 years of age.
The first commercial GSM call was made in 1991. Historical call was held in Helsinki between the former Finnish prime minister Harri Holkeri and Tampere deputy mayor Kaarina Suonio, who discussed the advantages of new technologies. The conversation took place in operator's "Radiolinja" 900 MHz GSM network. Organization of the Global Mobile Suppliers Association claims that at present in 234 countries there is 838 GSM networks, used by 4.4 billion subscribers. And this number encreases by one million every day. The GSM network covers 80% of inhabited Earth's surface.