We have seen Feedback Hub app in Windows 10 insider builds, to provide time to time feedback to the insider team sitting at Microsoft to help them to shape the Windows 10 OS to make it more better and better.
Now Microsoft is making available Feedback hub app to all Windows 10 users. This was first noticed by a french site TheWindose.fr. Now you can download Feedback hub app on any devices running any Windows 10 build and can submit feedback through it. However some of the sections of the feedback hub are not available for regular (non insiders) users, that are only available to insiders. You can download the app from below link.