T-Mobile UK

T-Mobile UK started life as Mercury One2One, a GSM mobile network operated by the now-defunct Mercury Communications. Later known simply as One2One, it was the world's first GSM 1800 network when it was launched in September 1993. In its final days it was operated 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. One 2 One was purchased by Deutsche Telekom in 1999 and rebranded as T-Mobile in 2002.

T-Mobile

T-Mobile offers both pay-as-you-go and pay-monthly contract phones. The pay-monthly contracts consists of set amounts 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 This was withdrawn in early 2010.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 HSDPAnetworks operated by T-Mobile UK and 3 was to take place starting January 2008. This will leave T-Mobile and 3 with the largest HSDPA mobile phone network in the country, with a theoretical maximum speed of 6.5 Mbit/s, rising to 7.2 Mbit/s over the course of the year, although HSDPA access is restricted to Web'n'Walk Plus customers and above.