If you no longer want an app to be available for users to install from the App Catalog, you can remove it. If any users have added that app to their sites, those app installations will remain. To remove an app from the App Catalog, follow these steps:

1. Navigate to the App Catalog site and select Site contents.
2. Hover over the app to remove, select the ellipsis (...), and then from the pop-up menu, select the ellipsis (...).
3. Click Remove.
4. Click OK to confirm the removal.

The app will be removed from the App Catalog. Users will be unable to add it to new sites but can continue to use and manage it.