Samsung Galaxy phones and tablets have just become the first consumer mobile devices approved by the US National Security Agency (NSA) to carry classified documents. The edict covers most of its newer Galaxy devices, including the Galaxy S5, Galaxy Note 4, and the Galaxy Note 10.1 tablet (2014 edition) -- as long as they're equipped with Knox, Samsung's mobile security app. Knox-enabled devices have already been approved by the US Department of Defense, but only for general, not classified, use. That's a shot of good news for Samsung in the face of recent dismal earnings, and it no doubt wants to translate the NSA's golden nod into consumer and corporate sales. Ironically, many of those potential customers may be paranoid... of the NSA.