Amazon is entering the wearables market in a big way.

The company on Thursday introduced a wristband for health and fitness tracking called Halo, alongside a subscription service and smartphone app.

The space is currently dominated by the Apple Watch and devices from Fitbit, which is awaiting regulatory approval for an acquisition by Alphabet’s Google. Amazon’s Halo product builds on these older fitness-tracking devices with features that have never been seen in a mainstream wearable device, including one that tracks a user’s emotional state by listening to the tone of their voice, and another that provides a three-dimensional rendering of their body with an estimated body fat percentage. 

It’s a departure for Amazon’s hardware business, which has previously focused on in-home devices, such as the Echo smart speakers and the Fire TV streaming video devices. Amazon showed off some wearable devices at its annual hardware event last fall, including wireless headphones and a set of glasses with built-in access to the Alexa voice assistant. But Halo is its first real shot at capturing a piece the fast-growing wearables market, which Gartner last year estimated would top $50 billion in 2020. 

The company has spent several years preparing. Amazon’s Melissa Cha, a vice president at Halo, said the company already had expertise around machine learning and computer vision, but expanding into health required a whole new set of hires.

“We did a global search to find the best experts,” she said. “We found cardiologists, fitness experts, and people who had spent their careers researching sleep and wellness.”

The company has stressed its commitment to privacy with this new device and committed that it won’t use the insights to sell health-related products to its users. But it is a way for the company to learn more about their users’ health habits and gather feedback along the way. 

It also ties in with Amazon’s broader efforts to capture a part of the $3.5 trillion health care sector. Five years ago, Amazon had no presence in the market. Since then, it’s added a team working on virtual health care offerings, known as Amazon Care, and joined Berkshire Hathaway and J.P. Morgan in an effort to transform employer health care. It has a health and wellness team under Alexa, its voice assistant, as well as a group focused on Covid-19. There’s also a secretive research and development “moonshot” team known as Grand Challenge, and a pharmacy-delivery group under PillPack. 

All of these teams could be pulled together into a health solution spanning devices, software and services. 

Helping people manage their help could also let Amazon build a deeper connection with customers. Health care is highly personal. If Amazon can build trust with users and get privacy right, while proving that it can improve people’s health care over time, it could unlock massive new revenue streams. The largest stakeholders in the industry, from health plans to employers, are all looking for ways to cut costs by keeping their populations healthier. 

The Halo device resembles a Fitbit tracker far more than an Apple Watch. It’s a simple design without a screen, with LED lights and two microphones. The device comes in a variety of styles, and Cha said it’s meant to be kept on all the time — it’s water-resistant for the shower or swimming, and it shouldn’t catch on clothes or bedsheets. There are also multiple sizes available for women with slender wrists. Cha said the company paid special attention to that, as many existing devices can feel overly clunky. 

The basic features of the Halo band will be familiar to anybody who’s used a fitness-tracker: It tracks motion, heart rate, sleep phases and skin temperature while sleeping.

At the same time, it provides a unique “points” tracking system that could be more effective than competitors in encouraging exercise. 

In the morning, users will see a sleep score out of 100 and a report showing their baseline sleep temperature.

Unlike Apple Watch, which encourages users to close rings, Amazon Halo uses a points system when tracking exercise. It sets a baseline goal of 150 points weekly, and users get more points for intensive exercise, such as running or walking up steep hills. Steps are automatically tracked, but users must manually enter certain other activities, like swimming. 

“This approach is more aligned with scientific guidelines,” said Dr. Maulik Majmudar, a cardiologist and principal medical officer with Amazon Halo.

Users who are sedentary for long periods — except during sleep — can also lose points. That’s a big difference from other products, which focus only on positive motivation. 

The battery lasts longer than Apple Watch at about seven days, in part because there’s no screen. The sole focus of the device is health and fitness, so there are also no features associated with making calls or accessing social media. 

Cha said the team had debates about adding other use-cases, like social media or e-commerce, but ultimately narrowed down the scope to health. “Our focus was in offering a service, with a wearable that felt like just a part of that.” 

But the device goes beyond traditional fitness-tracking with two unique features.

Tone is an optional feature that listens to the user’s voice throughout the day and analyzes that information to present a picture of how they felt — for instance, showing times they were feeling energetic, hopeful, or hesitant. For instance, the device might pick up on an argument, or a tense conversation at work, and indicate that the user felt elated at 10 a.m. but hesitant thirty minutes later. 

Amazon says none of the voice-based snippets are stored in the cloud and they’re automatically deleted once they’re processed. The company also said it won’t use the voice recordings for targeted advertising.

Body gives users a three-dimensional rendering of their body with information about their weight and body fat percentage. Measuring body fat percentage is typically difficult, but it’s a lot more helpful than the more widely used body mass index, which can mistake muscle for fat, leading to mistakes like labeling body builders as obese.

The Body feature uses the smartphone app, which guides users to stand in front of their phone in various positions, then takes photos from the front, back, and both sides. It then spits out a result in seconds. As users take scans over time — Amazon recommends doing one every two weeks or so — the Halo app generates a body model with a slider, which users can move back and forth to get a visual representation of their progress.

Amazon hopes ultimately to replace hydrostatic dunk tanks and pods, which typically require special access to a trainer or facility and are expensive, limiting them to athletesF and the wealthy. “We believe that everyone should has access to this important clinically relevant information about their own health,” said Majmudar.

The company said it tested the product on a wide range of body types, genders and ethnicities. Amazon stressed that the data can be deleted anytime and the images are automatically deleted from the cloud after they’re processed. But those who want to store their body scan images in Amazon Cloud can opt in to do so.

Users who have a specific goal in mind, such as weight loss, reducing caffeine consumption or getting better sleep, can opt to sign up to a challenge for a set period of time. Amazon refers to them as “Halo Labs,” and many of them include parnters such as the American Heart Association, WW (formerly known as Weight Watchers), Headspace, Mayo Clinic, and more. Amazon described these challenges as “science-backed,” meaning they are grounded in medical evidence. 

Halo also offers integrations with third parties — for instance, WW members who link their accounts will find that their Halo points translate to WW FitPoints. WW has a promotion for its members to get a free band and membership as part of its sign up process. There’s also an option to get a free device and three years of membership through John Hancock, a life insurer, for user that are willing to share their health information. (John Hancock also has a program with Apple, where policyholders can buy a discounted watch.)

Users who access their medical information via Cerner, one of the largest medical records companies, can also opt to share the health information gathered through Halo with their doctor. 

Unlike an Apple Watch or Fitbit, users can’t buy the Halo by itself — it’s only available as part of a subscription service. Amazon says this model could help the Halo avoid the fate of many wearables, which people typically use for a few months before relegating them to a drawer. 

Users will be able to buy a single band plus a six-month subscription for an up-front price of $64.99 during an early access period, which starts Aug. 27. (Eventually that price will go up to $99.99, but Amazon didn’t say when the early access period will end.) After the first six months, users will have to pay $3.99 a month to keep the service going. 

Style-conscious users can buy additional fabric bands for $19.99 and sports bands for $15.99. Those prices will also go up once the early access period is ended.