Here are iOS Objective-C headers as derived from runtime introspection.
The headers were produced using RuntimeBrowser for iPhone.
You can use the headers this way:
NSBundle *b = [NSBundle bundleWithPath:@"/System/Library/PrivateFrameworks/Message.framework"];
BOOL success = [b load];
Class NetworkController = NSClassFromString(@"NetworkController");
id nc = [NetworkController sharedInstance];
NSLog(@"-- IMEI: %@", [nc IMEI]);
You can search the headers with github search:
https://github.com/search?type=Code&q=repo:nst/iOS-Runtime-Headers+radar