So what exactly is 'Wifi calling?'
Simply put, Wifi calling is a setting on your phone, which once toggled means your phone will use Wifi for texts and calls if it offers a better connection than the mobile network at that point. It's completely seamless once enabled, and doesn't need an extra app to run (unlike using Skype or other VOIP apps). EE is the first UK network to offer Wifi calling, with other mobile providers expected to follow suit.
Testing it around the UK we've found it to be surprisingly powerful when paired with public wifi providers, allowing much higher quality calls than would be otherwise be possible in rural towns and the like.
Right, what's the catch?
Well, you'll be using your billable minutes and texts via the service, so on limited contracts costs could add up. EE have also been clear that at the moment roaming between wifi and the mobile network during a call isn't possible. So marching out of a coffee shop and out of wifi range will drop your call.
That's not much of a catch though?
Not really. Basically it'll mean you're contactable in more places, which could either be a positive or a negative, depending on the types of call you get. The biggest disadvantage for humanity is that phones will now work on the Tube (at least in stations). Great for a final 'I'll be home in 15' text, terrible for a quick followup from the boss on that important meeting.
How do I get it?
Apple users will need to update toiOS 8.3 first, then go to Settings >Phone > WiFi Calling and switch Allow WiFi Calls to yes. Android users will need to text "wifi calling" to 150, then allow wifi calls in options on their phone dialler.
What about older phones?
EE tells us that an update to allow Samsung Galaxy S5's to work on wifi calling is planned, and as EE are working with HTC it's quite possible that the One series will get the same treatment.
WiFi Calling is now expected to be available to 5 million people in the UK by the end of this month, according to EE.