Phil Zimmermann, the creator of Pretty Good Privacy, is widely considered the godfather of encryption software. After making his software available for download in the 1990s, he was the subject of a criminal investigation that was eventually dropped in 1996. Today, his P.G.P. software is the most widely used e-mail encryption software in the world.
But these days, Mr. Zimmermann is busy with his new venture, Silent Circle, which provides encryption for smartphone users. At a security conference in San Juan, Puerto Rico, Mr. Zimmermann introduced the service, which is available for Android and iPhone. Silent Circle lets users make encrypted phone calls, send text messages and do videoconferencing. Messages are scrubbed completely from the phone after a predetermined amount of time. Communications are secured using a new, peer-reviewed open-source encryption technology
His target market, Mr. Zimmermann said, is soldiers based overseas, business people who operate in known surveillance states, human rights activists, dissidents and (more recently) journalists. Since starting Silent Circle in October, Mr. Zimmermann, said, he has spent nearly all his time in Washington signing up government agencies and contractors.
He was adamant that the service be subscription-based. Individual users pay $20 a month, while businesses are charged per employee. He said he was often asked why people would pay to use the service when they could just as easily make free calls with Skype.
“I tell them go ahead and use Skype — I don’t even want to talk to you. This is for serious people interested in serious cryptography,” he said. “We are not Facebook. We are the opposite of Facebook.”
A large and growing number of people, including perhaps employees who don’t want their employers snooping at email or messages.