See http://developers.facebook.com/docs/authentication/canvas

A simple facebook graph api

This gem acts as a proxy for avatars on Twitter & Facebook.

Easy helper methods for adding custom social share buttons (Facebook, Twitter, Google+) to your Rails app.

Social linker generates share-links for the different social networks from a simple SocialLinker::Subject class. Supported networks are: Twitter, Facebook, LinkedIn, Google+, Pinterest, and email

Want to know how popular you are? This gem helps you look up how many Facebook friends and Twitter followers you have.

This Gem provides simple methods to add sharing functionality to your page. Currently supporting Facebook, Twitter Google+ and Reddit. Feel free to contact me if you want any features/services included!

Support for sessions tied to Facebook users.

StatsCollect is a little framework gathering statistics from external sources (social networks, web sites...), stored in pluggable backends. It can be very easily extended thanks to its plugins (currently include Facebook, Myspace, Youtube, Google).

A user class that is created with Facebook

This gem will allow your web application or mobile app to use tagging in a similar manner to Facebook or Twitter.

Easy event logger plugin for Rails 2.1. (Think: Facebook's recent activity feed.)

Get Facebook comments and save these in txt, csv file.

Adds social sharing buttons to video.js for Facebook and Twitter.

Wacky Graph is a gem extracted from Wacky Words Friends for using the Facebook graph API.

Wacky Canvas is a Rails 3 engine gem extracted from Wacky Words Friends for handling Facebook canvas app authorization. It records various stats for easy testing of new ideas and features.

A RubyMotion Facebook Wrapper, based of @clayallsopp's TwitterMotion wrapper.

This gem allows to easily access facebook's ads api in ruby. See https://developers.facebook.com/docs/reference/ads-api/

RFQL - Ruby interface for Facebook Query Language

Helper for add social share feature in your Rails app. Twitter, Facebook, Vkontakte, Odnoklassniki, WhatsApp, Viber