T-Mobile users get the premium version of At Bat 2014 for free
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