Across the pond in the UK, EE has been the one network to really push 4G adoption, of course they were allowed to go ahead with their plans before anyone else, but still they've made excellent progress since then. EE now covers most of the UK with 4G LTE and they're even working towards upgrading this already pretty speedy network with even faster speeds. Now, the network is looking to leverage this strong data backbone and test out voice-over-data using both WiFi networks found up and down the country and of course, VoLTE (voice over LTE).
EE's Test Lab will be working on a method for smartphones to search for WiFi networks, connect to them (if you have the right credentials of course) and then connect a call using the web. EE is looking to do this without the need for any sort of special app and is instead aiming to make the technology seamless for those using it. Such a technology would allow people to place a phone call in areas with no network coverage or just enjoy clearer phone calls when connected to WiFi. The more obvious choice for voice over data of course is the use of 4G. EE's Test Lab is looking to use their newly acquired 800 Mhz spectrum for VoLTE calls, as the 800 Mhz spectrum is in wider use across the country. VoLTE could be with us as soon as 2015 according to Fotis Karonis, chief technical officer of EE who said that when EE "have rigorously tested the performance of 4G calling and made sure that it matches our 2G and 3G quality, we'll launch it nationwide on our 4G network"
Using WiFi for calls is something that networks in the states have been doing for some time now and in the UK it'd make quite a bit of sense. Pretty much every coffee shop and shopping center up and down the UK has some sort of free WiFi and for pubs, coffee shops and places with poor network coverage (my local is bad for this) could still allow people to make a phone call using their free WiFi.