default
The country a phone field starts on when the caller names none, with its name in locale.
Deliberately the first entry of the English countries rather than of the localized list: "alphabetically first in the user's language" would silently change which country a field defaults to depending on the device language, which is a surprising thing for a default to do. Only the name is localized, so the field's helper and error text ("Enter a valid … number") read in the user's language from the very first frame instead of switching once they pick.