** UPDATE 11/12/09 : BOTH my wifi & network connection detection apps are WORKING Again! **
If you write an app that depends on internet access in order to function properly Apple requires that you detect the state of the connection and report it to the user when that connection is unavailable. If you do not Apple will reject your app on the basis that it is confusing to the user. Confusing because the app does not work and Apple assumes that the user will not understand why. Makes sense.
Here is one way to determine whether or not the users device has airplane mode enabled . . .
- Add SBUsesNetwork to the Info.plist
- Change its type to Boolean
- Add a check mark to enable
Here is handy little project that detects whether or not your application has access to a WiFi network:
Here is another handy little project that detects whether or not your application has any network access:
Download NetConnectDetection_3.0.zip
Feel free to use any of the above code in any way you wish. I am providing it in the hopes that it will help save someone from the headache that I experienced all day yesterday trying to get network detection to work 
If you find any errors or corrections please notify me and I will update the sample apps. Thanks!
