Google is redesigning its Google Play app store to make things easier to find and to streamline the way purchases work. (Courtesy of Google/Courtesy of Google)

Google announced a new look for its Play app marketplace, featuring bigger pictures and a simplified checkout system.

The company said in a blog post that the new format is rolling out Tuesday in the U.S. to Android smartphone and tablets running Android 2.2 (Froyo). International users should see the changes in coming weeks.

Apps, books and videos will be grouped by subject and feature more curated lists to suggest content specifically aimed at a given Google Play user.

On the company’s developers blog, Google explained how checkout will change: users can buy things from within an app without having to leave it and will also be able to see their app store balance when they make their purchase.

Apps are undoubtedly big business. Revenue for the world’s top app marketplaces hit $2.2 billion in the first quarter of 2013 alone, analysis firm Canalys firm said, with downloads across the major four app stores topping the 13 billion mark. According to the report, that’s roughly an 11 percent increase between the last quarter of 2012 and the first quarter of 2013.

The report looked at figures for Apple’s App Store, Google’s Play Store, the Windows Phone Store and BlackBerry World. Of the four, Google, the world’s most popular smartphone platform, had the largest share of apps downloaded, at 51 percent.

According to the report, however, Apple accounts for around 74 percent of the revenue that the four platforms generate — one reason why Google may be looking to make in-app purchases easier on the Play store.

Canalys analyst Tim Shepherd said that while Google and Apple are certainly the world’s top app stores, the Windows Phone Store and BlackBerry World also offer their own unique appeal to developers.

He said, however, that Microsoft and BlackBerry must work to increase device sales and get fresh and exciting developers to agree to develop for their platforms.

“BlackBerry World and the Windows Phone Store remain distant challengers today, though they still should not be ignored,” Shepherd said in a press release.

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