What is the black phone based on?

the available data:

The black phone is a smartphone that was developed with a strong focus on security and privacy. It runs on the Android operating system but has been heavily modified with custom security features like encrypted voice and messaging, anonymous browsing, and secure cloud storage.

The Blackphone 2 was released in 2015, followed by the Blackphone+ tablet in 2016. The company that produced these devices, Silent Circle, also offers a suite of secure communication apps that can be used on other devices.

The black phone's security features were developed in partnership with other privacy-focused companies like Geeksphone and Kryptus. It was originally marketed to individuals who were concerned about their online privacy, but it also gained popularity among government agencies and businesses that needed secure communication tools.

Overall, the black phone was designed to provide users with a more secure and private smartphone experience than what is typically available on mainstream devices. However, after a few years of availability, the black phone is no longer being produced and supported by Silent Circle.