Fitbit didn’t have a happy Christmas in 2016, as the novelty of wearables wore off somewhat. The tech startup’s sales slumped by 19% in Q4 2016 and Fitbit is planning to shedding more than 100 people from its workforce.

Amid the gloom, Fitbit this week announced details of its new heart-tracking wristband, called Alta HR. It’s a retooled variation on the pre-existing Alta wristband and, according to Fitbit, is the world’s thinnest wrist-worn tracking device.

Among the Alta HR’s features, it includes automatic exercise recognition, sleep tracking, up to seven days battery life and smart notifications. Alta HR is currently available for presale, with retail availability in April.

The device’s Sleep Stages function utilises heart rate variability to estimate the amount of time wearers spend in light, deep and REM sleep, as well as time awake each night. Sleep Insights uses collected Fitbit data to provide personalised guidance on how to improve sleep for the user.

Mini Chip

The Alta HR boasts PurePulse heart-tracking technology, not previously available on the Alta. According to the company, it developed a one-of-a-kind chip to house the technology in the new device, reducing the size and number of components needed. It also trimmed away 25% more in terms of device thickness compared with the Fitbit Charge 2.

James Park, CEO and co-founder of Fitbit, said: “The miniaturisation of our PurePulse heart rate technology opens up exciting opportunities for future generations of devices and new form factors. Our advances in sleep will provide millions of users around the globe accessibility to invaluable insights that previously could be obtained only through expensive lab tests.”

PurePulse allows users to measure all-day calorie burn and other heart-related metrics. Reminders to move, call/text/calendar notifications and other functionality is also catered for in the Alta HR.

The Alta HR costs €150 on presale, while the special edition version will cost €170. Different coloured and styled bands can be bought from €30.