Yesterday, both Facebook (NASDAQ:FB) and Microsoft (NASDAQ:MSFT) announced that Facebook Login is now available to Windows 8 and Windows Phone 8 developers. Though the move may seem like a simple one, it's yet another step for Microsoft to prove its ecosystem can compete with Android and iOS.

Facebook Login on Windows Phone. Source: Microsoft.

One login to rule them all
The Facebook Login is available for production apps on Windows 8 and 8.1 right now, and is in beta mode on Windows Phone 8 for the next 60 days. Microsoft said that three of the biggest apps that are first to add the login are Adobe Photoshop Express, Foursquare, and iHeartRadio.

It's no surprise that Microsoft would want to give the Facebook Login option to its developers. Facebook says that, when developers properly use its login option, user login conversion rates can be higher than 70%. That's important for Microsoft because getting users to log in to an app can be a huge hurdle.

Microsoft corporate vice president Steve Guggenheimer wrote on the company's blog yesterday that getting users to log in to an app can be one of the "largest blockers to trying a new app."

Aside from allowing users to access Windows apps with just a simple login, it also helps developers tap into Facebook's vast social-graph data. Guggenheimer said in the post that the social-graph data "can be used to enhance their applications' experience, enable new scenarios and open up the app to new customers, which results in better revenue opportunities."

More data, more customers, and better revenue opportunities are exactly what developers need from Microsoft's Windows and Windows Phone platforms. It's no secret the number of Windows Phone 8 apps lags far behind both Android and iOS app stores, and that developers are much more interested in making apps for those platforms. Though it's an incremental step for Windows 8 and Windows Phone 8, adding Facebook Login proves Microsoft wants to provide the same level of resources to its developers that Android and iOS already have.

Foolish final thought
Microsoft has been working furiously to beef up its app offerings, and to bring additional developers to its platforms, and adding Facebook Login is another good step. Earlier this year, the company provided Windows Phone developers with incentives to create apps, and earlier this month, Microsoft combined Windows Phone and Windows app developers into one account so that both groups could easily submit apps to both platforms. The catch-22 for Microsoft is that it needs solid PC, tablet, and Windows Phone sales to really get developers to pay attention to the platforms, while customers need to see great apps on those devices before they're willing to buy. Still, the addition of Facebook Login is a step in the right direction, even if it is a small one.