T-Mobile International AG is a holding company for Deutsche Telekom AG's various mobile communications subsidiaries outside Germany.
Based in Bonn, North Rhine-Westphalia, Germany, its subsidiaries operate GSM, UMTS and LTE-based cellular networks in Europe, Canada, the United States, Puerto Rico and the US Virgin Islands. The company has financial stakes in mobile operators in both Central and Eastern Europe.
The T-Mobile brand is present in 11 European countries – Austria, Croatia, Czech Republic, Germany (as Telekom), Hungary, Republic of Macedonia, Montenegro, the Netherlands, Poland, Slovakia and the United Kingdom, as well as the United States, Puerto Rico and the US Virgin Islands.
Globally, T-Mobile International subsidiaries have a combined total of approximately 150 million subscribers, making the company the world's seventeenth-largest mobile-phone service provider by subscribers and the third-largest multinational after the UK's Vodafone and Spain's Telefónica.
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