The 995 Audeo Mini is said to be the smallest and most advanced hearing aid in the world. About the size of a jelly bean, it is packed with sophisticated circuitry designed to adapt to changing "soundscapes".
The device can selectively focus on specific speech sources to reduce distracting background noise.
It also enables the wearer to detect high frequency sounds such as a birdsong or whispers.
Valentino Chapero, chief executive of Swiss hearing aid company Phonak, which makes the device, said: "The Audeo Mini is a landmark development for hear-ing correction and the next sig-nificant development in hearing technology. It is powerful enough to provide the user with crystal- clear sound quality while small enough to sit almost invisibly behind the ear."
One in five people in the UK has hearing difficulties and this figure is expected to rise to one in three by 2025.