UK mobile networks EE and Three are launching services to allow customers to make calls and send texts using only a WiFi signal.
Three will be offering its Three inTouch app in early August for all contract, SIM and pay-as-you-go customers, while EE will be rolling out its service from autumn 2014.
Enabling calling and texting through WiFi will be of particular benefit in rural areas, where poor phone signal can be a significant communication barrier for some mobile users.
Fotis Karonis, chief technology officer at EE, claims that the WiFi calling capability will be of the same quality as calls made through the firm's mobile network.
"The customer experience is seamless because it's the same as making a network call and uses the normal call interface of the handset," Karonis said.
"We're confident that this service can make a difference to people in homes and large offices across the country, especially in the most rural areas, that don't have mobile coverage."
4G phone calls
EE also announced plans to trial 4G calling using its recently developed VoLTE technology. Currently, those with access to 4G through EE can only use it for data services, with phone calls running off 2G or 3G networks.
"4G calling, or VoLTE, is an exciting technology that we're going to be trialling in the coming months using our low frequency spectrum, bringing one of the world's best voice and data services to a part of rural Britain that has previously been unconnected," Karonis said.
"When we 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."