Apple has filed a patent with the US patent office for smart headphones that can monitor physical activity, body temperature, perspiration and heart rate.

The patent also outlines gesture control from the headset of other paired devices and could either be developed within headphones themselves or attached to an existing set.

Unlike other wearable tech, the patent explains: “Advantageously, the invention can provide monitoring capabilities within a hearing device. Assuming the user is otherwise using the hearing device, such as to provide audio output by a portable media player, the user gains monitoring capabilities without requiring the user to wear or carry an additional article.”

The new device would use an accelerometer to measure movement and provide an output of activity via the user’s headphones. The invention has been devised by Chris Prest and Quin Hoellwarth, both employees in product design at Apple.