50 per cent of app revenues in the US are generated by just 25 developers, according to research by Canalys.

The App Interrogator survey found that these companies made $60m from paid-for downloads and in-app purchases over the first 20 days of November. 24 of them were gaming apps, while Pandora Radio was the only other to make the list of top grossing apps.

Zynga alone had 15 titles in the list of top 300 grossing iPhone apps and nine titles in the Google Play store. The top 25 includes cross-platform developers as well as mobile game specialists, including Zynga, EA, Disney, Kabam, Rovio and Gameloft.

Games accounted for 145 of the top 300 paid apps in the App Store and 116 in the Android marketplace. 94 of the top 300 listed free apps are games in Apples App Store, 110 in Google Play.

“Part of the story here is that successful game developers almost invariably have multiple titles generating revenue,” said Canalys VP and principal analyst Chris Jones.

“With the holiday season now underway, we expect to see many of these top game developers employing discounts and special offers, taking advantage of their ability to cross-promote within their app portfolios. This is expected to ensure that over the Christmas period in the US, the dominance of key game developers will only increase.”