iOS' security has come come a long way since the original iPhone. Its security has come so far, in fact, that the encryption is a nightmare for law enforcement trying to view information from devices seized from criminals for evidence. Apple uses an encryption method known as AES (Advanced Encryption Standard), which is a tough nut to crack. However, it's not just the encryption itself that makes iOS so hard to break into.
Originally Posted by Ovie Carroll
Most criminals aren't going to be dumb enough to not have a passcode since it keeps most people away from their sensitive information, however devices without passcodes take less effort to crack, since that is one less layer of security that needs to be penetrated. Unfortunately, even for a security expert, getting through the encryption is still a challenge when no passcode is present.
For criminals, the fact that iOS encryption is so secure makes the devices a great way to hide information from unwanted eyes, like law enforcement. Apple has always put heavy emphasis on user security from the part of their Web site that showcases their mobile operating system. As it appears, the gloating is certainly justified.
While the NSA might not be able to crack your iPhone’s security in a realistic amount of time right now, that’s not to say that they won’t be able to with future technology. Enjoy your high amount of security while it lasts.
Sources: Technology Review via Gizmodo