Annotate - Annotate (formerly know as Glui) is the simplest way to capture, annotate and share screenshots.
Greenshot - Greenshot is a free and open source screenshot tool that allows annotation and highlighting using the built-in image editor.
LabelMe Annotation Tool - LabelMe is an annotation tool writen in Javascript and Perl for online image labeling.
ShareX - ShareX is a free and open source program that lets you capture or record any area of your screen...
Monosnap - Monosnap is a comprehensive screenshot taking software system that provides users with a fast and accessible way to take screenshots whenever they want. Read more about Monosnap.
LightShot - The fastest way to take a customizable screenshot.