Clerk Chat - SMS for Slack
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.
Ray.so - Create beautiful images of your code
Feedback by Pixelic - Painless design feedback and version control.
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Sesov - A community for anonymous design feedback