Digitsole, a French start-up about to launch its first product on Kickstarter, has created interactive insoles that turn any shoe into a smart shoe.

The rechargeable insoles come with a smartphone app that allows users to track distance travelled, calories burned and even warm up their feet – completely wirelessly.

The Digitsole has been designed to fit into any shoe – from sneakers to ski boots – making it a more practical option for tracking daily activities than specially made smart-shoes.

The insoles are also better placed than other wearables to measure footsteps accurately, according to the designers: wristbands offer an approximation of physical activity, whereas each step is counted with Digitsole.

The insole weighs 3.5 ounces, has in-built Bluetooth 4.0 connectivity and can be individually controlled to warm up to 104°F. Pairs of the insoles are available for a Kickstarter pledge of $99 or more, and are scheduled for mass production in 2015.

For more on the latest developments in wearable tech, see our Health-Tracker Watch by Withings and Future Beauty: Wearables Nail Bar blog posts, as well as our influencer profile, Studio PSK: Pushing Boundaries.