Data:

When you make a copy of this application, you can choose either to retain the data contained in the tables, or copy just the structure of the application without the records. If you want to copy the application and retain the data, choose Copy this application with data. If not, choose to copy without data. If the app contains connected tables, these tables will not be connected to data services in your copy of the app.

Users & Roles:

In addition, you'll bring along all the users with whom you've shared this application. If you want, you can automatically grant them access to the new application in their assigned roles. To do so, choose the Copy users in their roles option. Please note that this action automatically grants these users access to the duplicate application. If that's your intention, you can then let these users know about the new application by going to its Manage Users page and sending them an invitation. If you don't want to share the new application with anyone yet, or expect to invite a different set of users, then select Copy users and roles separately instead.

Cross-App Relationships:

Maintain Cross-App Relationship: Leaves the Cross-App Relationship intact. This action does not add the Detail App to the Master Apps Cross-App Permissions. If you don't have admin permissions on the Master App, you'll need to request these permissions for this relationship to work properly.
Remove Cross-App Relationship: The relationship will still exist in the copy. If you inspect this relationship, you'll find that the Master App shows as "Unknown Table" and the relationship is Disabled. Later, if you change your mind, you can re-enable these relationships.
Grant Clone Access to Cross-App: You'll only see this choice if you have Admin permissions on the Master Application. Selecting this choice will add the Detail App to the Cross-App Permissions of the Master App.