Some highlights:
THE HOMESCREEN - Shows all of your teams, allows you to tab into a window displaying and constantly updating the real-time scores/stats, and also displays current fantasy relevant news.
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QUICK BOX SCOREBOARD - Shows your team vs. your opponents team by position. Constantly updates and allows you to check box scores as well.
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The app costs $4.99 in the market and is well worth it in my opinion. Chances are you have money riding on your league, so what's another 5 bills?
The bottom line is that if you play fantasy football, it better be on ESPN (no offense, yahoo). And if you play on ESPN, you need this app. So by the transitive property (told you I was a pre-med geek), if you play fantasy football, you need this app. Get it.