PGP creator Phil Zimmermann showed CNET an early version of Silent Circle's end-to-end encrypted VoIP client for iOS. "SECURE" means that the device on the other end of the conversation is also running the Silent Circle software. The words "newborn passenger" are randomly generated and can be read aloud for higher-security authentication if needed.
Silent Circle's app will securely scramble conversations -- using end-to-end encryption and the ZRTP protocol -- between two people using its software. If only one person has the app, as this photo shows, the connection will be scrambled only to Silent Circle's servers. That could still be valuable for overseas users worried less about the FBI and more about their own governments.