There are a plethora of iPhone app directories and platforms that try to make sense of the 100,000 apps in the App Store ecosystem. We’ve recently written about Appolicious, Chorus, and others that have customized app directory and recommendations services. Now, directories are beginning to incorporate Android app directories into their platforms. Mplayit, which recently launched a comprehensive iPhone app discovery directory within a Facebook app, is rolling out a catalog of the over 16,000 Android applications on the social network.

Similar to its iPhone app directory, Mplayit’s directory of Android apps includes a dedicated page for each app where Mplayit will post videos of the app (created either by the developer or pulled from YouTube), a detailed description of the app and reviews. You can also click to buy the app from the Android Market.

Once you start clicking on various app and downloading apps, Mplayit will begin to recommend apps to you based on your behavior on the site. And you can share apps on Facebook and Twitter. The Facebook page also shows the activity that’s taking place in other app marketplaces, such as Apple’s App Store or the Android Market, to show users what apps are receiving the most downloads, reviews and more. Users will also be able to see the “apptivity” within their social network, so they can clearly see what apps their friends and family are most interested in.

Myplayit is ramping up its offerings with the Android apps launched today, and the BlackBerry catalog added earlier this month. Mplayit also provides comprehensive tracking and real-time analytics to developers. developers to optimize their marketing for increased sales and social engagement. Other Android app directories include AndroLib.