LimeLite - A simple, easy-to-use annotation tool for Mac
ScreenTray - A better way to capture, annotate and share screenshots
LightTag - The text annotation tool for teams
Weava - Workspace to highlight, organize & collaborate on your research articles.
Good Annotations - A online annotation tool that is perfect for providing feedback to your team.
Marker.io for Slack - Turn screenshots into Slack messages ✌️