Nowaday, almost internet users have at least one account on social networks ( like Facebook, Twitter or Google Plus … ). Therefore allowing users log in your applications/sites ( apps ) via social network accounts is not only help users approach your apps easily but also help you reduce amount of work which is not necessary to focus to develop your apps.

Social Auth Plugin is the social authentication and authorization solution base on social networks for web applications. It helps you login using popular social network accounts.

Tampon is an open source Buffer app built as a Backbone.js application that communicates with a MongoDB datastore through a REST API written in PHP.

Tampon implements Buffer’s great original MVP: the ability to stock up tweets, choose a schedule, and have them shared automatically through the day.

PowerInbox, an interactive the email platform that enables users to run apps from inside their email messages. PowerInbox works on Gmail, Hotmail, Yahoo Mail and Outlook.

PowerInbox offers many email applications including Facebook, Twitter, LinkedIN and Groupon. Each app brings with it the ability to view and engage with site content from inside the email message.

Major Features

• Shop online inside your email
• Allow users to comment on a Facebook URL right inside email
• Allow users to Like, Tweet, and Share right inside email
• Add a Vimeo /Youtube video to your email template,  users can play it right in the email

Developers are also encouraged to build their own email applications, its open app platform makes developers create apps that run on all email using HTML5.

MiniTwitter is a free jQuery widget which adds Twitter and embed your tweets to your website or WordPress blog.

It not only put Twitter on your website but do even more by adding tweets from the folks you like, the lists and yourself. It shows up to 100 tweets within 7 days (limit set by Twitter’s Search API).

MiniTwitter comes in two flavors: a jQuery plugin and a WordPress plugin. You can limit the number of tweets displayed and it supports shortcodes for WordPress users.

• Use the color of your link profile on Twitter
• Display tweets from your feed or from the Twitter Search
• Display tweets from a list or from your favorite users
• Stylize your feed easily with your CSS

Greepit previously shared HybridAuth, a PHP library which offers website user authentication for social networks and popular sites.

Today, we are sharing Opauth, a multi-provider user authentication framework for PHP. It enables PHP applications to do user authentication with ease.

Opauth provides a standardized method for PHP applications to interface with authentication providers.

Opauth as a framework provides a set of API that allows developers to create strategies that work in a predictable manner across PHP frameworks and applications.

Social plugins let you see what your friends have liked, commented on or shared on sites across the web.

Koottam Social jQuery Plugin is a simple, powerful and elegant Social Media jQuery Plugin to display your social links. The plugin can be highly customized through 10+ options.

Major Features

• Counts directly fetched using API for Facebook and Twitter
• 7 themes + easy structure to add more themes in CSS
• Static or Animated count display
• Advanced option to change the coloring style
• Bigger counts cleanly shortened

Ospriet is a audience moderation app built on Twitter that allows for audiences to post and vote on questions/comments for talks, presentations, and events. The application is written in node.js, uses MongoDB for database storage, and is designed for deployment on nodejitsu.

Ospriet allows anyone with a Twitter account to submit a question or comment, by posting an @-reply to a Twitter account dedicated for an audience-oriented event. The submission will be reposted to the event’s account, with attribution. Audience members can vote up the best submissions by favoriting the submissions on the event account.

Ospriet will then keep track of all of the favorites and provide the top submissions. Ospriet provides one single, simple interface for all of this that audience members can use on most devices.

Twitter Follow Box is a simple but powerful jQuery plugin to add facebook like box style widget for twitter. Enough options are available to customize the twitter follow box widget to match your site design.

It is very simple to add twitter follow box to your site and this jQuery twitter widget is cross browser compatible.

jQuery ProQuo is a quick way to encourage your readers to spread your content through twitter. Simply define the regions in your markup that you would like to make “tweetable” and ProQuo will handle the rest.

Major Features

• Automatically determines proper text length and adds ellipsis in the tweet if the text needs to be truncated
• Includes a link back to the page that the quote was tweeted from
• Adds a “Tweet this” link to the tweetable element
• Auto-loads the Twitter widgets script if it’s not already available on the page

Twitter Bootstrap is a collection of flexible HTML, CSS, and Javascript components for popular user interface components and interactions.

StyleBootstrap is a free online tool to create custom and unique design themes for the popular Twitter Bootstrap 2.

StyleBootstrap offers an easy UI with so many options to help you create your own Bootstrap theme visually.

Recommended: jQuery UI Bootstrap – A Twitter Bootstrap-like Free jQuery UI Theme