AUSTIN, Texas--(BUSINESS WIRE)--T-Mobile US, Inc. (NYSE:TMUS):     What: The Un-carrier™ today confirmed its Extended Range LTE, or 700 MHz low band spectrum, which now carries T-Mobile’s LTE signals both farther and deeper indoors, is now live throughout Austin.   With a rapid deployment of a nationwide LTE footprint that reaches over 293 million Americans, “Bat City” is now lit up with T-Mobile’s best in-building coverage offering.   Extended Range LTE Coverage T-Mobile has been rolling out t