The app ecosystems supporting Android and iOS, the two most prominent mobile operating systems that account for the vast majority of today’s market share, have ballooned to include hundreds of thousands of apps each –  and app marketplaces are the key driver behind this growth.  A fresh study by app search firm Chomp looks into some of the recent trends in this space, shedding some light on the download statistics from the month of July.

Top search queries on Android encompass free apps, games and entertainment, while specific app searches seek out Dropbox, WeatherBug, Flash Player 10.3, Spotify and eBay.  For iOS,  games and entertainment also top search queries, with game searches being broken down across adventure and puzzle genres.  The apps iOS users are looking for include Tweetbot, Cut the Rope, Instagram, IMDb and Spotify.

As we can see, games and entertainment take priority for mobile users, as apps remain integral aspects of interaction on mobile devices.  This trend was also reflected in Millennial Media’s July report, where Android in particular brought in a large percentage of ad activity around mobile games.  Interestingly, we see Spotify maintaining a high level of interest on both Android and iOS devices, even weeks after launching in the U.S.  The personal cloud.

One emerging trend around mobile apps is the revenue it’s generating, as advertising, in-app purchases and other models expand on their monetization.  All in all, July saw two percent more spending on paid apps than June, and represented the third consecutive month users spent more in this category.

As existing app stores are seeing continued growth, new players are jumping aboard the bandwagon. Yesterday the Windows Phone Marketplace hit the 30,000 apps milestone, and today Skype – currently amidst the process of  being acquired by Microsoft– is launching its own app store.  The Skype Directory features dozens of free and paid add-on apps for Skype, including sharing and faxing utilities, and communication enhancements  to name a few.

Mobile trends on the consumer end are also empowering the enterprise, now that demand is accelerating.  Jive, a developer of social business software including an app store earlier this month, has been gaining from this boom and is a good indicator of the rest of the market.

The company filed for an IPO with the SEC today, hoping to raise as much as $100 million. The company is expected to hit $68 million in sales this year compared to n 2010 46.3 million in 2010.