The idea of this app is to give users information about cities such as the current weather, pictures, history, and cities that are around.

How can we do it? Firstly, we have to decide on how the app is going to suggest a city to the user. Of course, the most logical city would be the city where the user is located, which means that we have to use the Core Location framework to retrieve the device's coordinates with the help of GPS.

Once we have retrieved the user's location, we can search for cities next to it. To do this, we are going to use a service from http://www.geonames.org/.

Another piece of information that will be necessary is the weather. Of course, there are a lot of websites that can give us information on the weather forecast, but not all of them offer an API to use it for your app. In this case, we are going to use the Open Weather Map service.

What about pictures? For pictures, we can use the famous Flickr. Easy, isn't it? Now that we have the necessary information...