App Store account
You can sign in to the App Store using the following:
Apple School Manager or Apple Business Manager account: You sign in with the Managed Apple ID associated with your account or the Managed Apple ID associated with a purchaser you specify
Your personal account: This is the Apple ID you use to purchase personal apps
WARNING: If your Managed Apple ID account is already associated with an instance of Profile Manager, all app assignments from that association will be revoked. If your Managed Apple ID account is already associated with a third-party MDM solution, consult the MDM vendor before you log in with the Managed Apple ID associated with your Apple School Manager or Apple Business Manager account or the Managed Apple ID associated with a purchaser you specify.
View assignments
Choose Store > Sign In and sign in to the App Store with your Apple School Manager or Apple Business Manager account with privileges to purchase content.
Choose Window > VPP Assignments.
Click the disclosure triangle next to an app to view the serial number of the devices the app is assigned to.
Revoke assignments
Choose Store > Sign In and sign in to the App Store with with your Apple School Manager or Apple Business Manager account with privileges to revoke content.
Choose Window > VPP Assignments.
Click the disclosure triangle next to an app to view the serial number of the devices the app is assigned to.
Select a device from the list, click the remove button in the toolbar, the click revoke.
The app is now available to be assigned to another device.