From Facebook Developer Wiki

You're free to use the development environment of your choice when creating your applications. Choose from any of the following libraries.

[edit] Official Libraries

Facebook provides official support for the following libraries:

• PHP 5 -- http://svn.facebook.com/svnroot/platform/clients/packages/facebook-platform.tar.gz
• About the JavaScript Client Library | JavaScript API documentation index
• Facebook Connect for iPhone -- http://svn.facebook.com/svnroot/platform/clients/packages/fbconnect-iphone.zip
• ActionScript 3.0 Library for Facebook Platform -- http://www.adobe.com/go/facebooklibrary (officially supported with Adobe)
• Force.com for Facebook (officially supported with salesforce.com)

[edit] Third Party Supported Libraries

• .NET Facebook API Client - Supported by SocialCash

[edit] Unofficial Libraries

The Facebook Platform developer community maintains the following client libraries. Facebook does not provide official support for them.

• Android
• ASP.NET
• ASP (VBScript)
• Cocoa
• ColdFusion -- See also Developing a ColdFusion Application in 8 Minutes (video documentation and example downloads).
• C++
• C#
• D
• Emacs Lisp
• Erlang
• Google Web Toolkit
• Java
• Kontagent pre-instrumented libraries - Provides Instant to Kontagent Social Analytics w/o Additional Work
  • PHP - w/ Kontagent Analytics - Pre-Instrumented w/ Kontagent - a fbFund Company
  • Ruby on Rails - w/ Kontagent Analytics - Pre-Instrumented w/ Kontagent - a fbFund Company
  • Facebook Connect for Web w/ Kontagent Analytics - Pre-Instrumented w/ Kontagent - In Private Beta
  • Facebook Connect for iPhone w/ Kontagent Analytics - Pre-Instrumented w/ Kontagent - In Private Beta
• Lisp
• Perl
• Python
• Ruby on Rails
• Smalltalk
• Tcl
• VB.NET
• Windows Mobile