T-Mobile US Inc (NYSE:TMUS) is the only U.S. carrier to support Wi-Fi calls for iPhone 6 and iPhone 6 Plus at launch, but AT&T Inc. (NYSE:T)’s Ralph de la Vega confirmed his company will start support for this feature next year.

AT&T reportedly planning Wi-Fi calling in 2015

AT&T to enhance service for iPhone 6 users

This carrier has been a huge proponet for Wi-Fi. It even partners with other companies to provide public Wi-Fi access to customers. De la Cruz believes this will supplement and not boost network coverage. During a conference with investors on Friday, he added they don’t have a strong desire or even a need for coverage. He even threw a little shade at rival T-Mobile claiming operators with less coverage may be tempted to persue it more agressively.

Last Wednesday, T-Mobile talked about Wi-Fi calling and texting since Apple Inc. (NASDAQ:AAPL)’s new iPhone supports the technology. T-Mobile pretty much declared it is not the interest in Wi-Fi that prompted them to add coverage, it was more like “Why not?”.

How AT&T’s service differs from T-Mobile

AT&T will take a note from T-Mobile by offering calls that seamlessly hand off between the LTE network and Wi-Fi. However, the company has yet to launch the voice over LTE service and it even acknowledged that calls between the non-LTE and Wi-Fi service often drop calls. AT&T admits this is not a great user experience but still remains positive about its nationwide network.

De la Vega added that users won’t have to worry about a temporary bump in data. He said, “Those exploding offers — customers hate those offers. Unless they change their mind, we won’t offer those kinds of promotions.”

AT&T’s competitors such as Verizon and T-Mobile. The latter introduced a special four-line 10GB family data plan, however each line would lost 1.5 GB of data by next year. Following T-Mobile’s footsteps, Verizon added an extra 1GB of data to it’s plans which will last for two years.