T-Mobile UK was a mobile network operator in the UK. First launched as Mercury One2One (stylised one2one) on 7 September 1993, the network was originally operated by Mercury Communications. one2one was purchased by Deutsche Telekom in 1999, who rebranded it with their global T-Mobile brand name in 2002. In 1999, one2one became the world's first network to provide wireless network infrastructure to a mobile virtual network operator when Virgin Mobile was launched as a joint venture between one2one and Virgin Group. In 2010, it merged with Orange UK to form a joint venture, Everything Everywhere, in 2010, which continued to operate the T-Mobile and Orange brands until March 2015 and allowed T-Mobile customers to utilise Orange's 2G signal and vice versa. In 2012, Everything Everywhere launched their new network branding as EE. T-Mobile sims remain fully supported by EE, who are ultimately owned by BT since they acquired the company in January 2016 for £12.5 billion. History The network was originally launched as Mercury One2One, a GSM mobile network operated by the now-defunct Mercury Communications. It was the world's first GSM 1800 network when it was launched in September 1993. It was later rebranded as simply One2One, when it was operated for a short time as a joint venture between Cable & Wireless plc and American cable provider Mediaone Group, which had a number of investments in Britain dating back to its days as the US West Media Group. The network was purchased by Deutsche Telekom in 1999 and rebranded as T-Mobile in summer 2002. T-Mobile offered both pay-as-you-go and pay-monthly contract phones. The pay-monthly contracts consisted of set numbers of minutes and 'flexible boosters' which allow the customer to change them month to month depending on their needs. Prior to this T-Mobile had a contract option known as 'Flext' which gave the user an amount of money to use for calls, texts, MMS and mobile internet as necessary. This was withdrawn in early 2010. There is no warning when pay-monthly customers exceed their monthly inclusive limit, leading to unexpectedly large bills. T-Mobile launched their 3G UMTS services in the Autumn of 2003. On 12 December 2007, it was confirmed that a merger of the high-speed 3G and HSDPA networks operated by T-Mobile UK and 3 was to take place starting January 2008. This resulted in T-Mobile and 3 having the largest HSDPA mobile phone network in the country, with