Anti-spy technology remains hot a year after NSA leaks

More than a year after former National Security Agency contractor Edward Snowden leaked secret documents describing the breadth and depth of US surveillance, policy makers continue to debate the legal framework for such monitoring.

Yet a number of technology startups are blazing ahead to create a range of products that promise to restore people's privacy online. Silent Circle, WhisperSystems, and Wickr offer a variety of services, from private instant messaging to secure data storage to encrypted phone calls. Other companies, such as Blackphone, have focused on creating a secure smartphone for the privacy-conscious.

And even newer ideas are in the offing. A small Silicon Valley technology firm, for example, has designed a plug-in black box for smartphones that can encrypt a voice call on the fly and is seeking funding on Kickstarter. Called JackPair, the box can be connected between a smartphone and the user's headphones and encrypt conversations with another JackPair user, said Jeffrey Chang, founder of AWIT Systems, the firm behind the product.