App Store rankings rejiggered in move to iOS 6

Maps weren't the only thing to get a tweak with iOS 6. Apple appears to have changed how it determines the rankings on its App Store as well.

In a new post today (registration required), BTIG Research notes what it calls "dramatic" differences in the list of Top 25 free apps on Apple's App Store between yesterday and today, a period of time that also brought the release of iOS 6.

iOS 6 comes with complete redesigns of all Apple's digital stores, from iTunes to the iBookstore to the App Store. But there might have been some significant changes under the hood as well, BTIG Research's Richard Greenfield writes.

"While the iOS app store ranking methodology has never been fully disclosed by Apple, we believe it has been heavily influenced by the velocity of downloads, not overall popularity/installed base," Greenfield says.

As a result, some apps that were in the top fell off almost instantly, while others that were previously not in the Top 300 knocked off longtime placeholders. That includes apps from Zynga, Facebook, and Pinterest, all of which fell off the list. [Read more]