Jawbone has today launched the UP3 fitness band, a new activity tracker that measures sleep cycles and fitness metrics in more detail than ever before thanks to special electrical sensors that make contact with the wearer's skin.
As well as being able to track traditional metrics such as steps, activity and calories burned, the Up3 has the added functionality of being able to monitor heart rate and skin temperature, as well as three stages of sleep; rapid eye movement (REM), sleep associated with memory and high quality sleep.
Travis Bogard, vice-president of product management and strategy at Jawbone, said, "with UP3, our mission was to create the world's most powerful tracker in the smallest possible design.
"Our advanced, multi-sensor platform delivers a huge amount of new health data, backed by our smart algorithms and highly personalised Smart Coach system."
The wearable syncs via Bluetooth to iPhone and Android smartphones where the data is analysed to display health, activity and sleep measurements over various time periods.
This ability to measure sleep using a heart rate monitor gives the UP3 a major advantage over most other fitness trackers, as it enables much more detailed analysis of what has always been considered as important to physical health.
"If, for instance, we notice that you sleep better after a certain amount of exercise or steps in a day, we can suggest hitting that amount of steps regularly will improve the quality of your sleep," said Jason Donahue, project manager for data and insights at Jawbone.
Read more: Wearable tech market set for Christmas boom
"But going further, if you get a bad night's sleep with poor quality sleep we can detect this and knowing the hormones released after a bad night's sleep that make you crave fatty foods, can suggest better alternatives and help make the next night's sleep productive."
The device itself is actually quite nice to look at too and features an adjustable strap to ensure a snug fit. Arriving just in time for Christmas, the UP3 will set you back £149.99 and will be available in either black or silver.