Greenshot - Greenshot is a free and open source screenshot tool that allows annotation and highlighting using the built-in image editor.
Freshservice - Freshservice: the one-stop cloud solution for all your IT management needs.
Shutter - Shutter is a feature-rich screenshot program.
Freshdesk - Freshdesk is a cloud-based customer support software that lets you support customers through traditional channels like phone and email, social channels like Facebook and Twitter, and your own branded community
Snipping Tool - Use Snipping Tool to capture a screen shot, or snip, of any object on your screen, and then annotate, save, or share the image
Zendesk - Zendesk is a beautiful, lightweight help-desk solution.