Currently , full 3G network coverage in all stations and tunnels ( except West Rail Line ) for the MTR system has been provided by 3 Hong Kong , SmarTone-Vodafone and PCCW Mobile . Currently , full 3G network coverage in all stations and tunnels ( except underground section on East Rail Line and West Rail Line ) for the MTR system has been provided by 3 Hong Kong , SmarTone-Vodafone and PCCW Mobile .