Get the premium version of At Bat 2014 for free from T-Mobile
If you're about to upgrade to the premium version of At Bat 2014, and you're a T-Mobile customer, put that credit card back in your wallet. According to the carrier's support site, when you attempt to stream a live broadcast, you will receive an invitation from T-Mobile. Press the redeem button, and the nation's fourth largest carrier will pick up the tab for your premium version of At Bat for the rest of the season. The offer started on May 1st and ends on September 30th and apparently covers the iOS and Android version of the app only.
You might remember that T-Mobile offered its customers a similar freebie last year. The mobile operator has a special relationship with MLB, including a sponsorship of pitching changes. In some parks, T-Mobile has set up special 4G phones that connect from the dugout to the bullpen.
source: AtBat (iOS|Android), T-Mobile via TmoNews