The Holy Grail of sports tracking may have landed with the Kuai earphones. Unlike other offerings so far this offers everything in one package, without the need to carry a phone.

We've already seen heart rate monitoring headphones, earphones that store music, waterproof earbuds, and audio coaching – but never all in one place.

Kuai earphones are waterproof to three metres for swimming, store 8GB of music, measure heart rate and steps. They also connect to ANT+ and Bluetooth sensors like cadence sensors, ideal for cycling. That means you should be able to swim, cycle, run or gym train without your phone and still get audio feedback, music and recorded workouts. All that should keep going for five hours on a charge.

All the sensors feed into the Kuai brain where it works out what you need to do to hit goals. It'll read out information like lap times, speed, distance and more as well as telling you to speed up for slow down as needed.

Thanks to smart VO2 max calculations and heart rate monitoring the potential for future metrics is huge. Lactate estimates for example could be added with simple software updates as has been done on Garmin's latest Forerunner 630 GPS watch.

The Kuai multisport biometric headphones will be available this month for $150 now on pre-order but will be $250 when they arrive.

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