GKSession object will automatically handle the discovery of peers over WiFi or Bluetooth, and find those that are available on either protocol.
The documentation is stating that unlike Bluetooth, for which GKPeerPickerController provides a UI to enable Bluetooth if it’s not already enabled, GKPeerPickerController does not provide a UI to enable wifi, or select the network the user wishes to be on, you will have to provide your own.
Following example will help you
http://developer.apple.com/iphone/library/samplecode/GKRocket/Introduction/Intro.html
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