The content tab is used to share website pages with all the participants. Only moderators are able to publish pages.
In the Engagement app, a published page is a page that can be accessed by participants from the app. Unpublished pages are hidden from the participants.
For a page to be visible in the app (in Unpublished or Published tab), it needs to be published in the website builder first.
Please note: the Unpublished/Published tabs of the Engagement app work independently from the Website module in Azavista. Unpublishing a page in the App will not unpublish it on the actual website.