Moe Loubani

If you’ve ever wanted to draw on an image or add a caption or text to your image then this is the plugin for you. Best of all it allows you to add your caption, save it, display it, then go back and edit it in different layers and objects laid on top of your image.
It extracts the text from the annotations and displays them as selectable and stylable text just below.
You can hold shift as you draw rectangles to make them perfect squares, same with the ellipse tool and circles.

Image Annotator

This is a plugin that uses the HTML5 canvas and FabricJS to allow you to add shapes and text on top of images and display those images.

a-fiore

Adds inline annotations to WordPress using the Open Knowledge 
Foundation’s Annotator tool.
<h3>Features</h3>
<ul>
<li>Automatically includes the Annotator JavaScript code and its third party 
party dependencies (i.e. <code>jquery.js</code>, and <code>json2.js</code>) into the currently active theme (no HTML editing needed).</li>
<li>Offers the option to configure the annotable content area from the WordPress settings page.</li>
<li>Provides blog administrators with the option to decide whether to display only authenticated users’ annotations or also annotations made by anonymous users.</li>
<li>Provides a rudimentary regular expressions’ based mechanism for configuring in what pages/blog sections the Annotator widget should be included.</li>
</ul>

Annotator

Adds inline annotations to Wordpress using the Open Knowledge Foundation's Annotator tool.

Image Annotator vs Annotator