Boone Gorges

<a href="http://yourls.org/" title="Your Own URL Shortener" rel="nofollow ugc">YOURLS</a> is a free URL shortener service you can run on your webhost to have your own personal Bitly.
This plugin is a bridge between <a href="http://yourls.org/" title="Your Own URL Shortener" rel="nofollow ugc">YOURLS</a> and your blog: when you’ll submit a new post or page, your blog will tap into YOURLS to generate a short URL for it.
This plugin also features BuddyPress support. Short URLs can be generated automatically for each member and each group, and are customizable if permitted by the BuddyPress administrator.
Requires PHP 5.
Note: this plugin should still work but is no longer maintained. See http://yourls.org/#More#wordpress

YOURLS: WordPress to Twitter

Use YOURLS (a free GPL URL shortener service) to create short URLs of your posts, or for your BuddyPress groups and users

Ryan Street

Jason Grim

Background
WordPress has created the wonderful functionality of generating shortlinks for post on your blogs. With advanced 
permalink structures a single link to your site can take up 89% of a short email or a facebok update. However, 
Wordpress created a very ugly system, the shortlink system simply provides the default permalink structure with ugly 
url variables.
Here is the documentation on adding shortlinks to your themes on the <a href="https://codex.wordpress.org/Function_Reference/the_shortlink" title="Wordpress.org - Shortlinks" rel="nofollow ugc">WordPress Codex</a>
Use
Some themes use the template method to share the short url of your post. The use of this plugin would convert all of those 
links to trackable ones with bit.ly or shorter ones with the other services.
Also, when you create a new post a button is created next the the URL of your new post. If you click the “Get Shortlink” button 
a popup will provide a simple little link to share with all of your friends and fans.

Generate Shortlinks

Uses bit.ly, Ur.ly, and Is.gd to create handy shortlinks to share your WordPress Posts quickly and easily!

YOURLS: WordPress to Twitter vs Generate Shortlinks