O2 (UK) sale units, and with handset manufacturers, such as Apple and Samsung, to enable NFC technology on all future devices. On 23 February 2011, O2 announced it would launch a "second phase" for O2 Money, by discontinuing its branded cash cards in favour of a "mobile wallet" application for Android and iOS devices. The application would use NFC technology embedded in a phone to access money. It was announced on 9 January 2014 that the O2 wallet service would close on 31 March 2014. The BT Cellnet consumer brand was renamed O – the chemical symbol for an oxygen molecule –
O2 (UK) manufacturing Near Field Communication (NFC) technology in mobile phones in the United Kingdom. O2 and Vodafone signed a deal in June 2012 which will see the two companies 'pool' their network technology, creating a single national grid of 18,500 transmitter sites. Both networks will continue to carry their own independent mobile spectrum. In July 2012, O2 had to apologise to almost 8 million customers after a network switching subsystem failure led to a 24-hour blackout of the service across the UK and Ireland. The problem, which prevented a third of its customers' phones registering on the network, also affected customers