In the process of development, the functions of the GSM system are continuously enriched, so as to be able to provide more diverse services. The Short Message Service (SMS), which was first introduced by the GSM system, provides a novel, convenient and cheap communication method. In 1994, GSM implemented data services and fax services based on circuit switching. In 1999, the WAP protocol enabled users to access the Internet through mobile phones. The General Packet Radio Service (GPRS), which became commercially available after 2000, enables the GSM system to provide data communication in a more efficient packet manner. In 2003, EDGE technology was put into commercial use, providing a data communication capability close to 3G.
The GSM frequency band is widely used in mobile communications, so GSM jammers are also popular.