Contact support! Again, contact support! [20 chars ]
If IDE says it can’t delete because in use or installed by other users, then try to first remove the location of the app or device. It’s shown with a little “delete” - x to the right in the list. When the location is removed from the device /app it’s again possible to delete it. Works for me when I get that error
So when trying to save app I also get:
java.lang.NullPointerException: Cannot get property ‘Which?’ on null object @ line 44
this is on a fresh system with only 3 devices