An energy harvester device (30) located into an in-ear device (20) and harvesting energy from dynamic motion of the wall (14) of the outer ear canal (12) receiving the in-ear device (20) therein, with an external sheath (22) of the in-ear device (20) generally assuming the contour of the ear canal wall (14). The energy harvester device (30) has an energy harvesting module (32) mounting on an inner portion of the in-ear device (20) adjacent the external sheath (22), and is at least partially elastically deformable under a displacement of the ear canal wall (14) to generate energy corresponding to the displacement of the wall (14). An energy storage module (34) mounts onto the in-ear device (20) and connects to the energy harvesting module (32) to receive energy there from and supplying the stored energy to an electronic device of the in-ear device (20). The in-ear device (20) having the energy harvester device (30) therein is also part of the present invention.
