Marker.io for Slack - Turn screenshots into Slack messages ✌️
Usersnap - Visual Feedback - Usersnap helps your business with its versatile feedback platform to build better, more successful products and services with the help of user feedback. Collect feedback along your product development lifecycle. Try it for free.
Instashot - Access text from any image instantly.
Feedback by Pixelic - Painless design feedback and version control.
ScreenTray - A better way to capture, annotate and share screenshots
Sesov - A community for anonymous design feedback