You may have seen news from the US and UK about telcos offering Wi-Fi calling. In the UK, phone network EE has just started offering the service, while in the US, T-Mobile has had a similar service for a number of years.
But what is Wi-Fi calling and what's happening around it in Australia? To help make sense of it all -- and why you may want to use it when it becomes available -- we've put together a simple guide to talk you though everything you need to know.
What is Wi-Fi calling?
Instead of using your regular network connection, you can make voice calls using either the Wi-Fi you have at home or whatever Wi-Fi hotspot you happen to connect to when you're out and about. The idea isn't new: Skype and Google Hangouts, for example, already let you make voice calls using Wi-Fi, rather than your phone connection. What's different is that a Wi-Fi calling service provided by your telco shouldn't require a third-party app. In every other way it's like a normal call though -- right down to using phone numbers.
Both EE and T-Mobile allow you to send text messages over Wi-Fi as well. Keep in mind that both of these services count the calls and texts as part of your usual monthly limits, which will differ from plan to plan.
Why do I want that?
The main benefit is making calls when you have no phone signal. If you live in regional areas, for example, and find it difficult to get a phone signal, you can make calls and send texts using your home Internet connection instead. The same applies for when you're in those dingy, underground bars where your phone can't get reception, but can connect to the bar's Wi-Fi.
Isn't that what Skype does?
In a way, yes. There are various services that provide what's known as "voice over Internet," but a dedicated service is different. It's baked directly into the phone's dialler, so you don't need to fire up an app or connect to a service to use it. Once you lose phone signal, it will automatically switch to Wi-Fi calling.
That also means you don't need to add contacts to a service as you do with Skype. You'll already have access to all your existing contacts and, more importantly, none of them will require an app to receive your call.
Do I need a fast Wi-Fi connection?
Not an especially fast one. In the UK, EE reckons a 1Mbps connection will be sufficient for making calls over Wi-Fi. It'll apparently be possible on slower connections, but the quality will drop and it's possible you'll get some dropped calls too.
Do a need a special smartphone?
The idea of Wi-Fi calling got a boost of publicity last year when the iPhone 6 came out, but there are a lot of other phones on the market that support the feature. The list of phones that AT&T supports for its Wi-Fi calling services includes the Samsung Galaxy SIII, the LG G2 and even the Nokia Lumia 530.
That said, when it does launch locally, you'll probably need a small firmware upgrade from your telco to activate the service. As always, it's up to the telecommunications provider to decide which phones they'll build that for (which probably means Apple users will be safe).
Who's offering it in Australia?
Right now, no Aussie telcos are offering Wi-Fi calling. All the big telcos say that it's on its way, although we wouldn't recommend holding your breath. According to Vodafone, the network is "looking to formally commence a Wi-Fi calling project," but with the proviso that it's probably some way off.
In Feburary 2016 Telstra announced that it would rollout a 'Voice over WiFi' service as the complement to Voice over LTE. The service will seamlessly switch between home broadband WiFi and LTE for customers on compatible devices.
As of August 11,. Called WiFi Talk, the Optus service requires an iOS or Android app to be downloaded, making it distinct from a "baked-in" service. When using the app, Optus says that "calls and texts are charged to your mobile bill (or deducted from your prepaid balance) with the same inclusions and rates as your Optus mobile plan."
That's a lot of 'forward-looking' and 'developing' from the other two but Optus really did drop a bit of a surprise when it launched WiFi Talk so quickly. We'll keep this article updated as any new developments arise.
Updated on August 11, 2015 at 3.00 p.m. AEST: Added information about Optus WiFi Talk.
Updated on February 22, 2016 at 3.30 p.m. AEST: Added information about Telstra's Voice over WiFi.