Any agency user can create an app and then add it to the agency from the collaboration view for that app. At this point, it becomes under agency management. This means that if you're an admin and want to add a new app to your agency, you can simply create a new app and check the "add this app to the agency" checkbox during the creation flow.

You can connect an app to the agency at any time using the "add an app to agency" functionality in the collaboration tab. Adding that to an agency will not affect its collaborators unless you adjust them afterwards.

Quick Reference Guide

Adding a New App

When creating a new app, simply check the "add this app to the agency" checkbox during the creation flow.

Adding an Existing App

Use the "add an app to agency" functionality in the collaboration tab of the app settings.