When creating an iOS application, we often need to perform some actions based on the availability of an internet connection (WiFi, 3G, EDGE). To do so, the guys at Apple have created a nice little library that helps in that matter. Its name is Reachability.
To use this library in an iOS application, it is fairly simple. First, you have to import the following framework: SystemConfiguration. After that, you include Reachability.h in your code.