San Francisco: Tech giant Apple has hired top practical cryptography expert Jon Callas to bring more powerful security features for its products. Jon had worked with Apple in 1990s and again between 2009 and 2011. Jon Callas, who co-founded several well-respected secure communications companies including PGP Corp, Silent Circle and Blackphone, rejoined Apple in May, an Apple spokesman said.

His appointment comes after the US government recently broke into a terrorist’s iPhone without Apple’s help.

Callas designed an encryption system to protect data stored on a Macintosh computer. Callas has said he is against companies being compelled by law enforcement to break into their own encrypted products. But he has also said he supports a compromise proposal under which law enforcement officials with a court order can take advantage of undisclosed software vulnerabilities to hack into tech systems, as long as they disclose the vulnerabilities afterwards so they can be patched.