Whatis - Manage & organize your team's knowledge straight from Slack
userinput.io - Get on-demand feedback for your app, website or idea. Learn how to improve by hearing real opinions.
Slack-News - Read news from multiple sources within Slack by just typing
Upvoty - User feedback in 1 simple overview 🔥
Slack It - A bookmarklet to share links in Slack with one click
Instabug for Product Managers - Collect and understand user feedback