From Facebook Developer Wiki

[edit] Facebook Connect for Android

Port of the Facebook Connect for iPhone to Android platform.

http://fbconnect-android.googlecode.com

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Bloo is the de facto standard Facebook app for the Android [1]

A Facebook client for Android has been released to the Android Market. Screenshots: [2]. The app is called FriendMobilizer.

A developer has created a Facebook client for the Android platform.

This is not an official client library supported by Facebook.

[edit] FBRocket - Facebook SDK for Android

Lightweight implementation of the Facebook SDK designed from scratch purely for Android. Really easy for beginners, yet powerful enough for advanced for experienced coders. Integrates easily with your existing projects to bring Facebook features to your users. For example, changing your user's status is as easy as:

facebook.setStatus("is saying hello from FBRocket!");

Public preview 0.1 alpha now available: http://xeomax.net/fbrocket/