O2 (UK) BT subsidiaries: Esat Digifone in Ireland, Viag Interkom in Germany and Telfort Mobiel in the Netherlands. The rebranding was supported by a European advertising campaign, which began on 16 April 2002, across all four countries, at a cost of £130 million. The main launch campaign ran from 18 June and was developed by Vallance Carruthers Coleman Priest, working alongside brand consultancy Lambie-Nairn, creators of the "O2" brand identity. In March 2005, mmO2 restructured its shares and the company was relisted as O2 plc. On 30 November 2005, O2 agreed to a takeover by Telefónica, a Spanish telecommunications company, for £17.7
O2 (Ireland) available to customers paying similar amounts in the UK. Less than 48 hours after the much hyped launch of Apple's latest model, owners of all phones on the O2 network discovered they could not access the internet at all due to a network failure. Further criticism came from iPhone customers regarding the continued failure of O2 to deploy Visual Voicemail. O2 was the only carrier in the world to launch the original iPhone without Visual Voicemail, one of its headline features. O2 was responsible for the highest number of registered judgments, which financially blacklists those people who do not pay