aliasbdi

The User Social Fields plugin will allow users to add their social networking accounts to their user profile. Then, using a shortcode, 
a list of the user’s social web site links will appear on the page. The user can be specified or magically set (when viewing a page or single post). Additionally, 
the shortcode allows you to choose which social web sites to list and in which order.

User Social Fields

A simple way to add social networking links to your user profiles and display any where on your site with shortcode.

bitwit

The Postcard Social Networking Plugin for WordPress is designed to be compatible with Postcard for iOS. Without the companion 
app, this plugin won’t serve much purpose.
The intention of the Postcard app and plugin is to help users achieve a few key things:
<ul>
<li>Help users that want to post and display social content on their own website without any display restrictions</li>
<li>Help users create fresh content for their website when there isn’t time for long-form blogging</li>
<li>Help users that want to own their content by creating sharable permalinks that are attached to messages to networks like Facebook and Twitter</li>
<li>Help users drive traffic to their own websites</li>
</ul>

Postcard Social Networking Plugin for WordPress

This is designed for use with Postcard for iOS. Using shortcodes you can embed feeds and galleries of your content into posts and pages.

User Social Fields vs Postcard Social Networking Plugin for WordPress