In "Apps management" you can set the configuration and customization of the desired app. The "Maintenance" tab is the place where you configure possible downtime or scheduled maintenance of the app. Additional settings like "Settings" and "Permissions" is descibed here.
If you enabled the maintenance you can schedule one maintenance window for the app. You need to confiure the "Starts on" and "Ends on". You can add extra text to the standard "Notofication message". The default included text cant be changed.
If the maintenance window is scheduled, you will see the following indication in "Apps management". The user won't see the indication on the connected tiles.
If the app is under maintenance, you will see the following indication in "Apps management". The user won't see the indication on the connected tiles.
During the scheduled maintenance window, the tiles connected to this app will be greyed out. And the user will receive a notification message if they trying to open the app.