It's on sale because it will "expire" when the current season ends (Go, Sox!), meaning you'll have to purchase a new version for 2009. Still, if you're a fan and into the post-season, I encourage you to buy it. It's my hands-down favorite iPhone application.
While using At Bat, I realized how an application's features and benefits affect its longevity. Specifically, the features attract your attention, while the benefits grab you for good.
Here's an example. At Bat provides nearly real-time statistics for ongoing games, including scoring, current batter and pitcher, stats, the count at the plate ... even video clips from a game that's in progress.
You can identify your favorite team to keep their score highlighted, and enjoy an integrated version of MLB Gameday, which provides pitch-by-pitch information and so much more. All of this is presented in an attractive, readable UI.
Those are the features.
The benefit is a feeling of connectedness, even participation, and that's why At Bat is a keeper. As a die-hard baseball fan, I want to watch every game. I know the stats, the players, the standings; who's playing well, who's on injured reserve and who's in a slump. It's tremendously fun to watch a baseball game on a summer evening and get lost in the drama of it all.
However, life interferes (can you say "toddlers"?) and I sometimes miss a game. Yet, those live stats and video clips alleviate the feeling of missing the game, and that's worth a lot more than $2.99 to me.
The same can be said of other applications. Twitterrific [App Store link] puts 1,000 friends in your pocket (leave your adolescent joke in the comments, please). At any time, I can share a funny picture, observation or idea with my buddies, and get a reply just as easily. Those are the features. The benefit is the comfort of friendship.
The benefit of FileMagnet [App Store link] is peace of mind. Yes, I've got that PDF for the meeting. Yes, I've got the photo I have to show my boss. Phew.
Others that I've eliminated went in the other direction - all feature. Cro-Mag Rally's [App Store link] accelerometer-based steering got boring after 10 minutes.