I am new to iPhone development. I am developing an application in which I am using Settings.bundle which allows user to ON\OFF Wi-fi connection. Is there any way to turn ON\OFF device wi-fi when user changes settings from application settings??? I want to turn ON\OFF wi-fi based on changes to settings bundle.
It's not the job of your app to connect to the wireless! You can't alter the wifi settings of the iPhone from inside an application.
As far as I know, maybe jailbroken phones can do more.
You just Check Weather your phone is connected with Wifi or other network so http://developer.apple.com/iphone/library/samplecode/Reachability/ will be best place to start with. Have a look at the sample provided by Apple.