Since the new SDK was release (iOS 6), the delegate method documentInteractionController:canPerformAction: of the UIDocumentInteractionControllerDelegate<
Agreed on the fact that deprecating 'canPerformAction' in the delegate is troublesome, we lost the fine grain control we used to have.
However, if all you want is to allow a document to be opened in another app, and wanted to remove Copy, Print and even Mail, I guess you are better off using OpenIn version of method to present the UIDocumentInteractionController?
i.e. for your UIDocumentInteractionController use presentOpenInMenuFromBarButtonItem:animated: or presentOpenInMenuFromRect:inView:animated:
(instead of presentOptionsMenuFromBarButtonItem:animated: or presentOptionsMenuFromRect:inView:animated:)
This way, by default, it will only show apps that can open your document, and hides Mail, Copy and Print.