How to "Use Managed App Configuration with ArcGIS Enterprise"?

[TL2]

As mentioned with the new release you can now "Use Managed App Configuration with ArcGIS Enterprise" with Collector.  It is great that we are now able to do this, but some guidance as to how would be more than helpful.  Below is a screenshot from the Collector MDM settings.  I tried to follow the instructions for the Explorer for ArcGIS MDM settings setting "portalURL" as my Key and my portal url as my string.  did not work.

How do you do it?

[HECAdmin]

Is this possible with an ArcGIS Online tenant? I'd like to specify that the user's should use arcgis online and fill out the url part when they tap use enterprise login.

[ZorbaConlen1]

Hi. Is this capability available for ArcGIS Online? That is, can I use Meraki or similar to push out our AGOL url with installations of Collector or Explorer? Or is it just for Portal? Thanks.