U.K. and U.S. mobile consumers have probably noticed a lot of buzz from their carriers about Wi-Fi calling, which, simply put, lets you route phone calls over your phone’s Wi-Fi data connection using voice over IP rather than use the usual 2G network. It’s worth taking a look at some of these new services and how they differ from the regular voice services your carrier offers.
T-Mobile US and Sprint both offer support for Wi-Fi calling out of the box on newer Android handsets, the last two generations of iPhone and even a Windows Phone device here and there. Verizon and AT&T have both announced plans to offer voice over Wi-Fi this year. On the other side of the Atlantic, O2 and Three for some time have offered a form of Wi-Fi calling through their downloadable smartphone apps, Tu Go and InTouch, but we’re starting to see new services emerge from EE and Vodafone that will support Wi-Fi calling directly from the smartphone dialer. We’ve even seen U.S. cable companies like Cablevision use Wi-Fi calling to bypass the cellular network entirely offering a “mobile” service that operates exclusively on public and private hotspots.
To be honest, the carriers are a bit late to the party. In the last decade, we’ve seen the rise of any number of apps that utilize the internet, and by extension Wi-Fi, to bypass traditional telecom voice networks, from Skype and Google Voice to Viber and Tango. These apps made peer-to-peer communications – even across the globe – largely free, and they’re largely responsible for the big decline in traditional voice and messaging prices.
So what advantages are there to using a carriers’ Wi-Fi calling service? Savings-wise there really aren’t many reasons – in fact, some carriers still deduct Wi-Fi calls from your regular minute plan, making a service like Skype cheaper. But there are a lot of more subtle benefits.
- You use your existing phone number. Instead of downloading new software, creating a new ID for calling purposes or getting a new phone number, you use the same number and same smartphone dialer to make your calls. In fact, when working properly, you shouldn’t know the difference between a Wi-Fi and cellular call – your phone just switches between networks depending on which has the stronger signal.
- Strong signals are also a big plus because where Wi-Fi is the most abundant is often where cellular signals are the weakest. Think of your basement or that conference room in the guts of an office building: you may have trouble finding 2G bars on your phone, but your home or a building’s Wi-Fi network is pumping out strong signals.
- International roaming doesn’t carry a huge price tag. When a call is shunted off to Wi-Fi it’s taken off the cellular network, no matter where the cellular network happens to be. So when in a country where you’d normally have to pay a high roaming tariff, your Wi-Fi calls are either free or cost the same as they would at home, so long as you’re making a call within your carrier’s home network. Some carriers like T-Mobile US are even exempting international fees if you use Wi-Fi to place an international call to other countries.
So the proper way to look at Wi-Fi calling isn’t as a new type of mobile service. Rather it’s an extension of your existing mobile service making it more useful and sometimes cheaper, while keeping the convenience of a single phone number. And there are still plenty of kinks carriers need to work out. Wi-Fi calls aren’t truly mobile in the sense of a cellular call. If you move out of range of your Wi-Fi access point, there is no hand-off to a nearby tower – the call just drops.
As for quality, voice over Wi-Fi is still a toss up. Some carriers are upgrading Wi-Fi calls to high-definition (HD) voice, which dramatically increases the frequency range and amount of audio information sent over a phone call. But there’s a lot more than phone calls traversing the typical Wi-Fi network, and VoIP traffic has to compete for bandwidth just like any other application. That means a voice over Wi-Fi call on your home Wi-Fi network might have some of the best audio quality you’ve ever experienced on a mobile phone, but on a congested public hotspot, that same call might be unintelligible.
So my advice is to use Wi-Fi calling judiciously, using wireless networks you know will have the ample bandwidth to support a high-quality Wi-Fi call. For instance: your home and office WLAN or a trusted public hotspots (OpenSignal just launched a handy tool, WiFi Mapper, for finding them). But when you travel overseas, where the cost of making a phone call shoots up astronomically, use Wi-Fi calling wherever possible. In such cases, poor quality is a good trade-off for roaming fees.
Editor’s note: This is a guest post by Kevin Fitchard who is a journalist covering the mobile industry and wireless technology. He most recently wrote for Gigaom.