App Store - Method Swizzling Legality [closed]
AFNetworking, a lib widely (IMO) used for network-requests, used swizzling up to at least version 1.3.4 to support additional acceptable status-codes and content-types in class-methods.
So it seems legit to do it.
Note: They used class_replaceMethod and not method_exchangeImplementations.
Normally swizzling would be for debugging to see when a specific method is called, or in situation you can't subclass something or use a category for it. If you don't have a tight schedule on putting your Application on the app store, I guess you could try to send your application using method swizzling and see if it's accepted. No all application are reviewed the same way, sometimes it's just really up to the reviewer.