How can I reset the NSUserDefaults data in the iPhone simulator?

Question

You want NSUserDefaults removePersistentDomainForName. This will remove all user defaults for the application:

NSString *appDomain = [[NSBundle mainBundle] bundleIdentifier];
[[NSUserDefaults standardUserDefaults] removePersistentDomainForName:appDomain];

For more information on the NSUserDefaults class see the Apple docs.

Alternately, if all you are concerned with is data in the iOS Simulator, you can do that via iOS Simulator > Reset Content and Settings.

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