The company that shipped PrivatOS, SGP Technologies is a joint venture between the makers of GeeksPhone, and Silent Circle.
The concept of an encrypted phone had long been an interest of Silent Circle founder and PGP creator, Phil Zimmerman.
In a video on Blackphone's website, Zimmerman said, I had to wait for the rest of the technology infrastructure to catch up to make it possible to do secure telephony.
PGP was kind of a detour for me while waiting for the rest of the technology to catch up to make really good secure telephony possible.
Some major features of PrivatOS were anonymous search, privacy-enabled bundled apps, smart disabling of Wi-Fi except trusted hotspots, more control in app permissions, private communication (calling, texting, video chat, browsing, file sharing and conference calls).