How do I change a city?

In order to change the city default city (london), you need to click on "Settings" from the top of the menu bar and then click on "Change City". From the screen that's shown to you, click on "Select New City" tab and then if you're looking for Australia for example, from the Continent drop down list, select "Oceania". This will refresh the country list shown on the left side of the screen. Select Australia from there and then select a city from australia (cities are on the right side). Once you have found the city you want, click on "Add City". This will add the city to your saved cities list and will take you back to the main Saved cities list. Select the city you just added and then click on the "Select City" button at the bottom.