O2 UK is launching its Tu Go app the operator said will enable its users to make and receive calls, texts and voicemail via the Internet using their existing telephone number.
The service, available on all Apple and Android devices, is free to download for O2 contract customers, with the calls and texts taken from their existing bundle.
The aim of Tu Go is to free customers from being locked to a single handset, O2 UK product manager Caroline Dundas told BBC News.
"Customers can now take their mobile number wherever they like, even away from their mobiles," she said.
O2 UK customers can be logged into the Tu Go service on up to five devices at once, said the operator. Incoming calls will ring all logged-in devices, including handsets using SIM cards associated with different networks and Internet-enabled gadgets such as iPods, according to BBC News.
Commenting on the launch of Tu Go, Ovum telco analyst Jeremy Green said that the app is more than just another "me too" VoIP app by an operator. "It delivers tangible differentiation for Telefónica and is a lesson for its peers in integration with carrier telephony services."
"Only available to O2 UK's postpaid customers, it is a cloud-based telephony service, allowing the user to register multiple devices and make and receive calls and messages from all of these as if from their telephone number. Any usage comes from the user's postpaid inclusive bundle. TuGo can therefore be used regardless of physical location over Wi-Fi using the user's home contract. This also makes it an FMC solution, because it will work indoors on Wi-Fi at places where mobile coverage is poor," said the Ovum analyst.
O2 UK CEO Ronan Dunne told Mobile News the operator was able to offer the service thanks to its acquisition of VoIP service provider Jajah in 2009.
The app is notable since a number of European operators have complained of "over the top" (OTT) apps like Skype and WhatsApp cutting into their voice and messaging revenues.
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