Delete this room (×)
Screen: Rooms
What it is
The × at the right end of each room row. Its tooltip says Delete this room.
What to enter
Press it. A box opens asking Delete <room>? and lists what goes with it.
What it changes
In the app: Nothing until you press Delete room.
In the house: Nothing until you press Delete room.
If it goes wrong
Press Cancel if the list is not what you expected.