The \"Debug / View Debugging\" menu is always grayed out for me in Xcode 5 (and 6), even when the target is stopped at a breakpoint. How do I enable it?
Also make sure that view debugging isn't disabled in your current scheme's run options:
Xcode 6.1 still has the limitations about view debugging only working on 32 bit devices (iPhone 5 or older) and on iOS 8, though.