The wireless carrier is expanding its existing Wi-Fi calling and texting service with promises of more coverage in the home and in the air.
iOS 8's support for Wi-Fi calling means that iPhone owners will finally get in on a feature that Android and Windows Phone owners have had for years.
The carrier has confirmed that the Google Nexus 5 will not support voice over a Wi-Fi network.
Though support documents posted this morning suggested the Nexus 4 could support Wi-Fi calling, T-Mobile has confirmed that the Android phone will not have the feature.
Blame Jelly Bean, but one of the carrier's most popular features will not be present for the "Pure Google" LG Android smartphone.
AT&T exec Ralph de la Vega also says he expects customer turnover to remain near record-low levels in the current quarter.
The Personal CellSpot is an all-around excellent home Wi-Fi router with no monthly fees that also works very well with Wi-Fi calling.
Pricing not available
The low-cost waterproof smartphone joins a growing roster of devices capable of making phone calls over Wi-Fi.
CNET editor Dong Ngo explains how Wi-Fi calling works with the latest smartphones, including the iPhone 6 and 6 Plus, and picks the top five routers that are best for this technology.
T-Mobile USA offers the UMA Wi-Fi calling feature on several more Android phones. An earlier version of this story incorrectly said that the feature was limited to two phones.