What happens when you search for a popular genre of games on the App Store? You might expect the most popular game to show up first. But that’s not always the case, especially with the hot category of mobile social casino games, according to new search tracking tool startup SearchMan.com.

Search rankings are important because they are the No. 1 way users find apps, according to Nielsen. Optimizing your app for search is a more affordable way for indie developers to get their apps noticed than buying mobile advertising at relatively high prices, says Niren Hiro, co-founder of SearchMan.com, which specializes in optimizing mobile apps for discoverability. You can think of search as the “shelf space” of the digital age. And on Apple’s new iOS 6 (the new version of the operating system for the iPhone, iPad, and iPod Touch), Apple has removed the categories button from the main screen of the iPhone 5 and left search intact.

SearchMan.com found that lesser-known game studios including Avanlix, Aristocrat, Arawella, and Pokie Magic have an extraordinarily large number of apps ranking inside the top 250 search results for gambling-related search keywords in the App Store. Hiro said that results inside the top 250 are visible to users. Zynga is known to be interested in the social casino games genre, but it also has aggressive competition from Backflip Studios, TinyCo, Big Fish Games, and others. The search results are based on the number of appearances of apps published by a specific game company in the top 250 search results for four gambling-related keywords: casino, gambling, slot and poker. The keywords were chosen based on the highest query volume in the U.S. App Store, as estimated by Google Keyword Tool.

As you can see in the chart below, Aristocrat has far better search results than Zynga in the top 250.

SearchMan.com has delivered its search tracking tool and analysis to more than 2,000 developers since launching three months ago.