Mobile operator O2 is to provide free internet to "millions" of residents and visitors in central London by launching Europe's largest free wi-fi zone.

BBC: 'Europe's biggest' free wi-fi zone set for London

MACH's Direct Billing Gateway provides an operator billing service for mobile applications, content and mobile internet services, allowing providers to charge subscribers for services direct to their mobile phone bill or pre-paid balance.

ENGADGET: Skype strikes deal with Mach to expand direct carrier billing for credit purchases

At the moment only mobile operator EE is able to offer customers the 4G service, which provides faster mobile internet connections.

BBC: 4G to affect TV reception in two million homes