30 Seconds of Knowledge - Become a better developer, in every new tab.
userinput.io - Get on-demand feedback for your app, website or idea. Learn how to improve by hearing real opinions.
Random User-Agent - Automatically change the user agent after specified period of time to a randomly selected one, thus...
Upvoty - User feedback in 1 simple overview 🔥
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Instabug for Product Managers - Collect and understand user feedback