T-Mobile US, Inc.
T-Mobile US, more simply known as T-Mobile, is one of the largest wireless network operators in the US, providing wireless voice and data services, and host network for multiple mobile virtual network operators. Its majority shareholder is Deutsche Telekom, one of the largest German companies.
The market capitalization of a company, more simply referred to as "market cap", is the total market value of a publicly traded company's outstanding shares. It is often considered as a key indicator of what a company is worth.