T-Mobile International AG
T-Mobile International AG is a German holding company for Deutsche Telekom AG's various mobile communications subsidiaries outside Germany. Based in Bonn, Germany, its subsidiaries operates GSM, UMTS and LTE-based cellular networks in Europe, the United States, Puerto Rico, and the U.S. Virgin Islands. The company has financial stakes in mobile operators in both Central and Eastern Europe.
Globally, T-Mobile International subsidiaries have a combined total of approximately 230 million subscribers. T-Mobile International is the world's fifteenth-largest mobile-phone service provider by subscribers and the fourth-largest multinational after the UK's Vodafone, India's Airtel, and Spain's Telefónica.