This is apparently a reliable way to assure security from a compromised OS on your personal device against surveillance offering the users to go “black”, as described by Edward Snowden:
All phones today utilize software to separate, turn on or off these features. Software can be hacked or compromised in many ways or inadvertently made to allow apps have free reign of permissions which can leak your metadata. With PRIVAT you know your videos, photos and location can be separated from possible surveillance when needed.
The Privat phone is currently being funded by their Indigogo campaign for a very reasonable price. It will be interesting to see the development of this phone as it is soon to be rivaled by the McAfee Privacy Phone which will also provide physical switches to turn off hardware. It appears the McAfee phone will go one step further by providing a means to protect against IMSI catchers.
Unlike the Copperhead OS phone, it appears GooglePlay will be provided with the OS. However since the physical switches do not rely on software, you should be able to flash your own custom ROM and still utilize the physical switches like the phone was intended. There is not much more information we can provide you in the early development stages of PRIVAT. We will update this page when more information becomes available. Their Indigogo page has more detailed information about this phone.