The beta release of iOS 9 includes a Wi-Fi Calling feature specifically for AT&T Mobility customers. Until now, only T-Mobile and Sprint subscribers have had access to the service, which was added to iOS 8. According to MacRumors, AT&T has begun rolling out the service to a "limited number" of subscribers with iOS 9 installed on their iPhones.
Browsing the web or sending text messages while on a phone call has been a feature of GSM networks like AT&T's for some time. Now thanks to the rollout of Voice over LTE (VoLTE), Verizon customers can get into the game. Later this year, the company plans to begin offering the service for compatible devices.
The next iPhone is expected to launch with iOS 8, which will include VoLTE capabilities. Verizon has been implementing the network upgrade nationwide, which will also bring improved HD Voice quality to compatible devices. The iPhone 5 and 5s are both designed to take advantage of HD Voice, and other carriers are working on deploying the technology.
Wideband audio was showcased by Apple at the iPhone 5 keynote, however T-Mobile is the only US carrier to support the technology. This is all set to change later this week, when AT&T rolls out HD Voice on its Voice Over LTE (VoLTE) network starting Friday. HD Voice will be enabled on the Samsung Galaxy S 4 mini first, with more devices to follow.
Both the iPhone 5 and iPhone 5s will support HD Voice, which expands the frequency range heard during a voice call. This reduces background noise and provides more natural and realistic sound, making caller's voices easier to hear. According to an AT&T press release, the first markets to receive the upgrade will be in Illinois, Indiana, Minnesota and Wisconsin.