You can archive app items by designating them with a specific category, then filtering them out.
Step by step, you should:
- Modify your app template and add a Category field. This is only required if your app doesn't already have a Category field
- Add categories such as "Entered", "In progress", "Completed", and "Archived"
Pro Tip: Use the color picker on the right of the categories to select colors for each category. - Select the "Archived" category for any items you would like to archive
- Filter out your archived items so that they no longer appear in your app view. Click the filter icon at the top when viewing your app. Then find the Category field, and select to show every category except for "Archived"
- Click "Save view" so that other members in the workspace can use this view as well
Note that the items will still exist within your apps, so they are still able to be used in relationship fields, and they will be shown when your filter is not enabled.