Create beautiful changelogs or release notes
Once a request has been completed it should be part of your product changelog. Though in-app popup messages and changelog pages inform your users of new updates or announcements. Therefore you keep informed of how your product nicely evolves.
Show your latest releases in a beautiful changelog in a text or timeline view, including the requests and features you ship in each release. Each changelog entry represents a new release, which can include the feature / requests set that is shipped in the that release.
Add a widget in your web app to show in an elegant and unobtrusive manner your latest updates. Integrate that widget in your app is as simple as adding a little snippet in the code.
Allow your users to subscribe to your twitter or Slack channels, or Mailchimp subscribers list. So once there is a new release they receive a proper notification. Keep your users in your product loop.