Devices with stereo speakers deliver sound from independent channels on both left and right sides, creating a richer sound and a better experience.
Resistance to sweat makes it ideal for use while doing sports.
The device is protected with extra seals to prevent failures caused by dust, raindrops, and water splashes.
The device comes with its own special case or pouch, which is useful for safe transportation.
The in-ear device is ultracompact and lightweight, with little or no interference with earrings, spectacles, hats, or hairstyles. It is inserted in the ear canal itself and blocks out a lot of environmental noise. It has stronger bass tones and is unlikely to fall out of the ear.
The cable is designed to minimize tangling.
An L-shaped plug is better if the jack is on the left or right side of the device, so that the cable isn't bent, and is less likely to break when the device is in your pocket.
A coil cable offers more flexibility, as it can be further extended when in use, as well as retracted to take up less space when not in use.
A long cable ensures more freedom of movement.