The market for “full catalogue” app stores has reached its limit, with only a few players joining in 2011, as new entrants have instead opted to focus on niches, according to research2guidance.

The company said that 2010 was a “watershed year” for app store openings, with more than 30 joining the race, many of which were intended to offer a full range of apps. However, “only a few” of these managed to attract enough developer attention, while others that may have looked promising at launch “succumbed to market pressures and closed, combined their offerings or were slowly fizzling out at the close of 2011.”

In contrast, Apple’s App Store and Google’s Android Market (now Play Store) have continued to gain momentum, adding new content and seeing increasing volumes of content downloaded.

research2guidance said that “at this point, any new market entrant will need to provide something fundamentally different to what Apple and Google are offering, or invest a significant amount of money (eg Microsoft’s investment in the development of Windows Phone Marketplace).”

The company noted that “niche app stores blossomed in 2011,” numbering nearly 100 by the end of year. The focus of these vary from OS-specific, to “quality curation,” to consumer groups such as enterprises.

One opportunity it suggests is through the opening of web app stores, driven by the wider of adoption of HTML5. Mozilla, for example, has opened its own marketplace which, while focused on desktop web apps, will complement its smartphone HTML5 efforts.