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. The T-Mobile brand is present in 12 European countries – Austria, Croatia (as Hrvatski telekom), Czech Republic, Albania, Germany (as Telekom), Hungary, Macedonia, Montenegro, the Netherlands, Poland, Romania, Slovakia, and the United Kingdom, as well as the United States, Puerto Rico, and the U.S. Virgin Islands. 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.