How Facebook is doubling down on mobile

Facebook's (FB) announcement Wednesday of its new Messenger mobile app is big news among software developers eager to build tools that integrate with the product.

But Facebook isn't just souping up an app. This is about the social network providing an alternative to mobile platforms from Apple (AAPL) and Google (GOOG), as well as building an ecosystem that tethers users to Facebook.

On the surface, Facebook has decided to enable partnerships with many development companies, small and large. For developers, that represents getting access to hundreds of millions of users, while for Facebook it's a way of effectively outsourcing the development of a range of Messenger features. And users will get some immediate benefits, like adding music to messages or sending images instead of plain text. Companies will also be able to use Messenger to communicate with consumers.

But the capabilities will be much broader. Facebook has already added a payment button to Messenger. Users can send money to friends, and future versions of the software will likely let people pay companies for goods and services.

Perhaps the most compelling reason for Facebook to enhance Messenger: finding new sources of revenue. Rates for online advertising -- the company's main source of income -- are sliding, while Facebook's ubiquity puts it in good position to take small cuts of online payments.

As important is the recognition that Facebook's future is mobile. Increasing amounts of its traffic comes from people on smartphones or tablets, so the company wants as much control over a mobile platform as it can get. To that end, it has previously pushed for a Facebook phone as well as Facebook Home, which acted like a top access level for an Android smartphone.

The new version of Messenger may give Facebook a way around the platform dominance of Apple and Google. By incorporating communications, third-party extensibility and its own brand, the company may hope that it can build what would effectively be a super-platform, riding atop whatever mobile system people use. That could create something that no platform owner could afford to ignore or try to push out of the way.