In the first quarter of this year, Microsoft's (MSFT 1.82%) Windows Phone OS outpaced BlackBerry (BB 1.80%) and nabbed the No. 3 spot OS market share. As 2013 has progressed, Windows Phone market share has only gotten stronger -- while BlackBerry continues to struggle.

While BlackBerry isn't out of the fight yet, there are two reasons BB10's chances are running thin: apps and ecosystem.

Good is good enough, for now
Let's get this out of the way first: Windows Phone has an app problem. Microsoft has about 160,000 apps in its Windows Phone Store -- while Apple has just shy of one million, and Google's Play Store has more than one million. Not only are there more apps in the two leaders' app stores, but Windows Phone users typically don't get an app until after iOS and Android get it first -- think Instagram and Google Maps.

Windows Phone App Studio screenshot. Source: Microsoft.

To help battle its app problem, Microsoft just launched the Windows Phone App Studio for non-programmers to create apps in a web-based WYSIWYG environment.

But even with its meager amount of apps -- compared to Android and iOS -- Windows Phones still have more options than BlackBerry's OS. Right now, BlackBerry has about 100,000 apps in its store and, as of the end of March, about 20% of them were apps ported over from Android. BlackBerry boosted its apps count by paying developers to port Android apps to its OS -- rather than build them from scratch -- but the company stopped the porting incentives at the end of June. While the program helped build BB10's app offerings, it still hasn't fixed the problem of developers not wanting to create native apps for the platform.

Windows on my mind
The other lingering issue for BB10 making any gains against Windows Phone is the fact that Microsoft's products – and essentially its ecosystem – is vastly more prevalent than BlackBerry's.

Microsoft may not have hit a home run with Windows 8, but at least the vast majority of the global PC users still boot up some version of the company's operating system everyday. On top of that, Microsoft has the Xbox and Surface tablets in its overall ecosystem.

As with the apps, Microsoft doesn't offer the best ecosystem or devices -- but it does offer more than BlackBerry. The combination of Microsoft's devices, software prevalence and ecosystem help keep it at the forefront of consumers' minds. The company may not be the first or second choice for mobile users, but it safely owns the third spot.

The challenge going forward for BlackBerry isn't just to sell lots of BB10 phones, but to create products that prove to consumers that BlackBerry is a strong tech brand worthy of consideration. As it stands right now, BlackBerry loyalists may still see it that way, but BB10's drop from 4.9% global market share in the second quarter of 2012 down to 2.9% year over year proves that it's clearly moving in the wrong direction.