ESPN's Scorecenter iPhone App is the top sports application in iTunes, alongside several other successful ESPN apps: ESPN Radio ($2.99), ESPN Fantasy Football ($2.99), ESPN Zoom ($2.99), ESPN Streak for the Cash, ESPN 2010 World Cup, and so on.

Paid mobile apps are a key part of ESPN's digital strategy:

“I think we are evolving into a mobile applications world, which offers much more personalization, and we’re moving towards more paid content in mobile,” said John Kosner, senior vice president and general manager of digital media at ESPN, Bristol, CT. “We take it for granted that content is free on Web sites, but I think you’ll see something different evolve on mobile. “We’re committed to multiple revenue streams, and Apple’s iTunes billing and carrier billing makes it easier to do paid mobile content,” he said. “Advertisers want scale, and we’re able to provide that by delivering want fans want.

“It’s all about value—fans will pay for content that they value and they can’t find other places, and we’ve also been able to reach scale and have enough of an audience mobile so it interests advertisers.”

The focus on mobile applications is evident from the advertising and cross-promotion online, on-radio, in-print, and even on-air. Listen to an ESPN radio broadcast and you will hear several personality-driven promotions of the new ESPN Radio App... and, if you visited yesterday, you surely noticed that the homepage was taken over to promote ESPN's Scorecenter application:

Traditionally, ESPN saves the homepage for high CPM, rich ad units; here, they are promoting a free application for mobile users. That app is then used to promote ESPN's paid applications (average of $2.99 per download) through overlays, interstitials, etc. It is an interesting move considering that the holiday shopping season just concluded and that iTunes is seeing record traffic post-Christmas.

The ad unit is terrific: it takes over the entire background of the page and features a 'swiping' finger. As the finger swipes between iPhone screens, ESPN's background synchronously shifts. It is great looking and does an excellent job showcasing the slick UI on the iPhone.

click to see each 'stage' in full size