O2

O2 is a major wireless telecommunications brand and was the original exclusive carrier for the iPhone in the United Kingdom.

History
O2 was originally formed by mmO2 in February 2002, with mobile coverage in the UK, Germany, Ireland, and the Netherlands. O2 became the exclusive UK carrier of the iPhone when it was launched in 2007. The exclusivity agreement expired in late 2009.

The brand is presently operated by, a joint venture of and  which merged their UK businesses on June 1, 2021. On July 1, 2021, O2 began shutting down its 3G network in phases across Germany to make room for faster 4G and 5G services. O2 will shut down its 3G network in the in November 2021.