As someone who has spent most of my working life in London, I have come to accept the lack of mobile connectivity in Zone 1 tube stations. Likewise, patchy mobile coverage at home is something that I tolerate. Making or receiving mobile calls standing in specific spots and rooms has become second nature.
Wi-Fi calling (VoWiFi) provided by my mobile operator is changing all this. Last week I answered a call from a colleague while standing on the platform at Westminster underground station – it took me a while to register that my phone was ringing. And now at home I have mobile coverage everywhere. The voice call quality is as least as good as cellular, although I do seem to have more dropped calls.
VoWiFi is not a service that mobile phone users have been crying out for – or indeed one that mobile operators have been pinning their hopes on to drive new revenues. Indeed, it was Apple that first supported VoWiFi last year with the launch of the iPhone 6, and most operators were initially cautious about its adoption. But in practice it is one offering that can make a tangible difference to the quality of service provided by a mobile operator.
Until now, network coverage as a differentiator has been defined by how far mobile connectivity reaches into rural and remote areas. Now, with Wi-Fi calling, differentiation is based more on the quality of in-building coverage. This is as likely to be an issue in urban as in rural areas.
The extent to which Wi-Fi can be seen by mobile operators – and mobile users – as a complement to cellular services, rather than as an alternative form of connectivity and therefore a disruptive technology, varies based on the respective usage case and operator business model.
Wi-Fi has a number of positives for operators. When Wi-Fi is an application on a cellular-enabled device (MiFi, router, tethering), it is a positive because it drives usage and connectivity. For the mobile retailer, the popularity of Wi-Fi-only devices (principally tablets) helps sell more devices. And for the operator whose priority is to contain traffic levels, Wi-Fi is a cost-effective approach to offloading traffic from the mobile network.
But there are negatives. The ubiquity of (free) Wi-Fi in homes, offices, and increasingly in public places makes it difficult for operators to persuade customers to spend more money on data or buy cellular-enabled tablets. Furthermore, there is no real evidence that people are using proportionately less Wi-Fi as they migrate to LTE and use more data.
Telecom operators often complain about the fact that the so-called OTT providers get a “free ride” over their networks. When it comes to Wi-Fi calling, it is the mobile operators who are getting their own free ride on fixed networks. And it represents an opportunity to leverage Wi-Fi rather than feeling undermined by it.
T-Mobile USA has been the biggest operator evangelist of Wi-Fi calling, using it as an important part of its Un-carrier strategy, which has seen it dent the dominance of AT&T and Verizon Wireless. But other LTE operators globally are set to launch in 2016.
Interestingly, while VoWiFi launches are gaining momentum, the progress of voice-over-LTE is more stuttering. Both VoWiFi and VoLTE require the operator to deploy an IMS platform, and operators that roll out both services will enable their customers to roam between the two. But whereas VoWiFi has a clear value proposition, it is not quite so clear how VoLTE benefits the end user.