When the Pantech A1407PT cell phone is placed against the jaw, the mechanical vibration from the phone is conducted to the inner ear, which responds normally.
The result: the user hears the other person on the phone perfectly.
Engineers at Pantech say a phone that uses bone conduction provides additional advantage to the user.
As the sound is conducted directly to the inner ear, it becomes easier to hear conversation in a noisy room, they say.
According to a Live Science report, engineers are only one step away from developing a truly futuristic phone, which can be attached directly to the skull behind the ear, under the skin - as suggested by science fiction writer Robert Heinlein in his 1951 novel, 'The Puppet Masters'.