Tap the New City icon at the bottom of the screen
to select another city for your list.
Tap the Delete icon at the bottom right corner
of the screen to select one or more cities select a city to delete
from your list.
Tap the Menu Key to delete all of the cities
in your World Clock list.
Tap and hold an entry in the list to open a Context menu to select Set DST (Daylight Savings Time) or Delete.