HA, NabuCasa, supporting App are all more or less setup for one instance and one location. What if you have multiple ‘homes’ which you would like to control/automate? As in home, holiday location, weekend house, apartment, office, workshop, etc… on different locations with different networks?
Try it with Remote-Home-Assistant integration and you start crying tears to get the connections established (and don’t count on the documentation because that is seriously limited for an average person).