jesperb

<blockquote>
The core concept with Fronted is that theme and plugin developers incorporate their configuration filter and/or add-on in their plugin or theme. However since version 1.3.5, it will automatically configure itself to make <code>post_content</code>, <code>post_title</code> and <code>post_thumbnail</code> editable if no other options are set.
</blockquote>
<a href="http://fronted.westart.se" rel="nofollow ugc">Live Demo</a>
<a href="https://github.com/jesperbjerke/wa-fronted/wiki" rel="nofollow ugc">Documentation</a>
<a href="https://github.com/jesperbjerke/wa-fronted/issues" rel="nofollow ugc">To report bugs or feature requests, please use Github issues</a>

<h4>Features</h4>
<ul>
<li>[x] Support for extensions and integrations</li>
<li>[x] Supports Custom Post Types</li>
<li>[x] Supports Custom Fields (see <a href="https://github.com/jesperbjerke/wa-fronted/wiki/Supported-fields" rel="nofollow ugc">supported fields</a> for more details)</li>
<li>[x] Advanced Custom Fields support (see <a href="https://github.com/jesperbjerke/wa-fronted/wiki/Supported-fields" rel="nofollow ugc">supported ACF fields</a> for more details)</li>
<li>[x] WooCommerce support for simple product types (see <a href="https://github.com/jesperbjerke/wa-fronted/wiki/Supported-fields" rel="nofollow ugc">supported WooCommerce fields</a> for more details)</li>
<li>[x] Supports <a href="https://github.com/fusioneng/Shortcake" rel="nofollow ugc">Shortcake</a></li>
<li>[x] Utilizes TinyMCE (thanks to <a href="https://github.com/iseulde/wp-front-end-editor" rel="nofollow ugc">isuelde</a>)</li>
<li>[x] Autosave</li>
<li>[x] Post revisions (step through and see changes live)</li>
<li>[x] Live value validation</li>
<li>[x] Automatic oEmbed conversion upon paste</li>
<li>[x] Automatic url to link conversion</li>
<li>[x] Image upload by dropping an image into the editable area</li>
<li>[x] Drag image to move it within the editable area</li>
<li>[x] Automatic changing of image size to load when changing size of image in content</li>
<li>[x] Edit featured image</li>
<li>[x] Shortcode rendering & editing</li>
<li>[x] Show unsaved changes warning if leaving page</li>
<li>[x] Ability to edit other common columns from the posts table</li>
<li>[x] Ability to set post as featured</li>
<li>[x] Ability to set post parent to hierarchical post types</li>
<li>[x] Ability to edit custom excerpt</li>
<li>[x] Allow/Disable comments</li>
<li>[x] Ability to edit fields saved in the wp_options table</li>
<li>[x] Edit and add taxonomies (both custom and native)</li>
<li>[x] Basic RTL support</li>
<li>[x] Choice-based fields with dropdown-select</li>
<li>[x] CTRL + click on link in editor to open in new tab/window</li>
<li>[x] Automatic config of <code>post_content</code>, <code>post_title</code> and <code>post_thumbnail</code> if no settings are set, can be turned off by setting <code>auto_configure</code> to <code>false</code></li>
<li>[x] Check/Set post locks</li>
<li>[x] Possible to create new posts from frontend</li>
</ul>

WA Fronted

A frontend editor for WordPress. Free and open source project with a goal to enhance usability and convenience of editing content.

nektobit

A lightweight (8Kb minified, 2.9Kb gzipped) script to let users share their text selections to social networks, in desktop browsers. (Yes, like Medium). 
Based on Sharect.js
<ul>
<li>Supports adding custom icons (for now using php snippet)</li>
<li>You can also control the color of the tooltip widget (also using php code)</li>
</ul>
<a href="https://nektobit.github.io/WP-Sharect/#documentation" rel="nofollow ugc">Documentation</a>
Millstones
The plugin is under active development, I welcome any feedback.
<ul>
<li>Add widget color picker</li>
<li>Adding social media icons from the admin interface</li>
<li>Optional meta tags</li>
</ul>

Sharect WP

The plugin allows you to highlight text on your website and share it on social networks

WA Fronted vs Sharect WP