Apple has announced that its App Store now holds over 100,000 apps, highlighting the company's dominance over the also-rans. That includes Google's Android Market and its comparatively paltry 10,000 apps, although Android has had less time on the market.

"The App Store, now with over 100,000 applications available, is clearly a major differentiator for millions of iPhone and iPod touch customers around the world," said Philip Schiller, Apple’s senior vice president of Worldwide Product Marketing. "The iPhone SDK created the first great platform for mobile applications and our customers are loving all of the amazing apps our developers are creating."

What makes the feat even more impressive is that Apple was able to accumulate all these apps in just 16 months. There's definitely something to be said for being the first major player.

Of course, quality is just as important as quantity, and here too Apple has been making strides to improve its App Store. Features like Genius recommendations, App Store Essentials, and sub-category listings are all efforts to give quality apps their due.

While the mobile world -- or at least the media -- remains fixated on Apple's iPhone OS, Google's Android platform, and the Blackberry OS, let's not forget that Symbian is still the market share leader, and now it has an app store to boot, the Symbian Foundation announced at the Symbian Exchange and Exposition 2009 (SEE 2009).

The "Horizon" app store is now live and kicks off with 50 apps, some of which included YouTube, Twitter, and Qik clients. But that's just the beginning, as the mobile OS outfit hopes to have thousands more in 2010 as developers sign up to have their apps listed in the Symbian Horizon Directory.

"We recognize that developers face many challenges in bringing their products to market on Symbian devices," said Lee Williams, Executive Director of the Symbian Foundation. "In particular, the diversity of application stores in our ecosystem increases the burden on developers by requiring multiple submission and review processes. But this diversity can also offer an advantage over competitors' closed systems, where applications sometimes receive arbitrary or commercially motivated rejections. Symbian Horizon retains this advantage while reducing the burden by becoming a conduit to multiple stores, helping developers reach the largest global mobile market in the world more effectively."

Several Symbian platforms already have their own app stores, including Nokia's Ovi, Samsung's Application Store, and Sony Ericsson's PlayNow platform, and all of these will support Horizon and integrate its apps into the mix. And while it's far too early to make any meaningful predictions, the question on everyone's mind is whether or not Symbian might actually challenge Apple's App Store, which is now over 100,000 apps strong.