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BT Mobile has upgraded its network in a way that brings it a lot closer to the big UK players, as it’s launched both Wi-Fi Calling and VoLTE (Voice over LTE, also known as 4G Calling).
These two technologies are somewhat similar, in that VoLTE lets you call and text over 4G, while Wi-Fi Calling lets you stay in touch over Wi-Fi.
The advantage to this is that previously if you only had a 4G signal or only had a Wi-Fi network but no mobile signal you wouldn’t be able to send and receive texts and calls, but now you can, and it works seamlessly using your normal dialler and SMS app.
Wi-Fi Calling in particular could be useful indoors, where mobile signal sometimes struggles to penetrate, but where there’s often a Wi-Fi network. If you have any signal blackspots at your home or office for example this essentially solves them.
4G Calling meanwhile has an additional benefit in that it can offer superior sound quality than calls over 2G or 3G. And you can continue to use 4G data at full speed to download things or run apps while using VoLTE.
Limited availability
Both services are available to all new and existing BT Mobile customers, but to use them you need an iPhone 6 or later, or a Samsung Galaxy S9 or Samsung Galaxy S9 Plus bought from BT Mobile. We’d expect more handsets will be supported over time though, so if you don’t have any of those phones you might not be out of luck.
BT Mobile isn’t the only network to offer Wi-Fi Calling or VoLTE, as EE, O2, Three and Vodafone all offer both, but most MVNOs (Mobile Virtual Network Operators) don’t, so BT Mobile stands out from rivals in that sense.
