Now, in the age of the smartphone, Boeing is developing a real-life device that deletes all its call and message data if any unauthorized attempt is made to crack it open.
Boeing's device is one of two stealthy new "Black phones" that were revealed this week, both targeting privacy-sensitive customers who want to hide below the radar of the growing surveillance of mobile communications.
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Boeing already runs secure communications for the U.S. president's Air Force One aircraft and is pitching its device at government officials and their contractors.
Meanwhile, start-up Silent Circle, in a Swiss-based joint venture, is hoping to tap growing demand among consumers and enterprises for extra protection from prying eyes, in the wake of privacy revelations by Edward Snowden, the former NSA contractor.