MLB At Bat 14 free for T-Mobile subscribers
I searched the webs earlier today for this, knowing that last year T-Mobile made an announcement on May 1. I found what I was wanting to hear...
"UPDATE: As the official sponsor of Major League Baseball, we will be offering MLB At Bat 14 to our customers for free starting May 1 through the entire regular season! With our unlimited data and nationwide 4G LTE, you can enjoy all the great features MLB’s At Bat has to offer!"
Anyway, if you're on T-Mobile, download the AT Bat 14 app, then when you go to sign up you'll be greeted by Magenta.