Leave it to ABI Research’s Competitive Assessment of Mobile Application Storefronts to try and sort out not only who owns the best storefront, but also to find a way to actually quantify this and provide a comparative measure. ABI has done so, though its findings are not likely to prove all that earth shaking. Part of the problem of course is that in truth there actually aren't that many app stores to put up against one another.

Yes, there is of course the original beast, that being Apple's. And then there is the Android shop, now dubbed Google Play. Microsoft has certainly stepped up its app store game with the release of its various versions of Windows 8. There is the Nokia Store that features a range of Symbian apps, but that's going to go away very soon. Amazon has its own app store, as does Samsung, but neither showed up as winners in ABI's research. And of course we have Research in Motion (RIM), which at the end of November 2012 issued the amazing news that it had rechristened its app store from BlackBerry App World to…BlackBerry World -- surely a subtle change. More interesting for RIM is that the company should have at least 100,000 well-qualified apps there when it launches its new BlackBerry 10 OS and new devices at the end of January.

ABI's conclusions are based on findings that are drawn from the research firm's Mobile Application Markets Research Service. The service focuses specifically on the distribution and the economics of mobile apps, providing data-driven insights on areas such as download volumes, revenues and business models, plus trends within different applications categories.

For the app stores themselves, ABI takes a look at a variety of issues. At the topmost level are the categories of overall implementation and overall innovation. Each category in turn is underpinned by various factors. For the implementation category ABI looks at effective approaches to monetization, market share size across the app industry overall and the ability to achieve a large inventory of titles while maintaining a reasonably strict quality control.

For the innovation category ABI looked at capabilities such as app discovery overall solid usability. Discovery is an area that has been given significant importance for the simple reason that when a customer arrives at an app storefront much -- if not all -- of the following download activity, if any, will be based entirely on how the vendor presents and highlights its inventory, especially through various charts. The easier something is to discover -- and just as important, the relevance to the shopper of what the shopper is able to uncover through that discovery process -- the better the chances of the user completing a purchase.

Given the above criteria, Apple has won in terms of overall app store implementation, coming in ahead of both Google and RIM. ABI senior analyst Aapo Markkanen notes however that “Although Apple has done a great job capitalizing on the App Store’s head start as an app distributor, it should really start re-thinking the way it charts the top apps."

Apple was narrowly beaten out by Microsoft on the innovation front, with Google claiming the third spot. ABI Research is particularly impressed by Microsoft’s fresh approach to app discovery. We should note here -- although it has nothing to do with ABI's rankings -- that Microsoft has been diligent in significantly improving not only the quality of its store but also the number of apps that are now available within it -- which is now sitting somewhere in the neighborhood of 35,000 apps -- a significant and worthy achievement since the store has only been up a few months.

Markkanen continues, "Microsoft should be lauded for its initiative to extend its ranking algorithm beyond raw download figures, by including factors that can actually measure the customer satisfaction and retention. Retention-based charts are less prone to manipulation, so as an additional plus Microsoft can also afford being more transparent about its approach. Moves like this can help break the developers free from the ‘tyranny of downloads,’ decrease their reliance on costly marketing campaigns, and thus lower the barriers to entry.”

Of course Apple and Google continue to dwarf the competition in overall app numbers, with Apple well over 700,000 and Google pushing in just below Apple, but also above 700,000. All told Apple itself has actually approved over one million apps for the store, although many of these approved apps obviously never made it into the store.