iOS

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  Universal (iPhone + iPad)

  MLB.com At Bat

  get itFree

  If you're serious about baseball, $14.99 per season is a bargain for this app's live audio of every game, copious highlight videos, and condensed games. If you're a casual fan, the free version will keep you up-to-date with live scores.
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  Universal (iPhone + iPad)

  Sunday Ticket

  get itFree

  Three words: Red Zone Channel. If you've got DirecTV's Sunday Ticket package, get this app now, and you may actually be able to leave the house on Sunday during football season.
• 
  Universal (iPhone + iPad)

  ScoreMobile

  get itFree

  Get updates on every team you follow, in every sport (even MMA and European soccer). ScoreMobile can send you push alerts on every scoring play, final scores, and lets you group players together so you can track your fantasy teams in real time.