MLB’s At Bat App Downloaded More Than 400,000 Times’s mobile strategy is adding to — not cannibalizing — the league’s traditional web business, according to President and CEO Bob Bowman. Speaking at the Apps for Brands conference in New York yesterday, Bowman shared some stats about MLB’s At Bat app and announced a new feature coming to the service in time for the playoffs (hat tip to Ad Age).

Bowman said that the $9.99 At Bapp app, which allows users to stream live games to their iPhone, has been downloaded more than 400,000 times, and MLB’s free app has been downloaded more than 350,000 times.

Unlike MLB’s other subscription products, which are used once or twice a week, customers are using the mobile app “every day,” said Bowman, because they’ve always got their mobile device on them.

MLB is also set to launch a Quad View feature for the At Bat app in time for the playoffs, which will let users view a game from four different angles, simultaneously. Without having seen the app in action, this seems like it will involve a lot of squinting on such a tiny screen, but I’ve learned to never underestimate the nuttiness of baseball fans.

We’ve heaped our fair share of praise on MLB before, and this is just the latest example of how it’s embracing new video technologies — an approach that’s paying off for the league. Earlier this summer it made MLB.TV available on both Boxee and Roku.