A web API (back end) and an iPhone game (front end) that let you find out which of your Facebook friends you know the best by quizzing you on their interests.
"If your application connects to the network, it's important that you provide the appropriate error messages when the network is not present. See the Reachability iPhone program sample which demonstrates the use of the System Configuration Reachability API to detect the absence of WiFi and Wireless Wide Area Network (WWAN) services, so that you can notify your users that a network connection is not available. Your application can then take appropriate action at the first point where network services are required."
"If your application connects to the network, it's important that you provide the appropriate error messages when the network is not present. See the Reachability iPhone program sample which demonstrates the use of the System Configuration Reachability API to detect the absence of WiFi and Wireless Wide Area Network (WWAN) services, so that you can notify your users that a network connection is not available. Your application can then take appropriate action at the first point where network services are required."
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