Challenges for expansion
If you are inclined to take further what you have learned in this and previous chapters, you may wish to expand and improve the app in the following ways:
Add the same functionality to the iPhone app, but present much more of the wealth of information provided by http://openweathermap.org/.
The UI is a very Spartan one, you should be able to find any number of tweaks that will make your version of the app look a thousand bucks more expensive.