Skip to main content ( (AMZN) - Get, Inc. Report) is getting into the wellness business with the strangest activity tracker on the market. But don’t worry, a bigger plan is afoot, and it’s super bullish for the company.

The Halo is an activity tracker without a screen. The wrist-worn device, announced Thursday, is the front end of a larger system that includes 3D body scanning and anxiety tracking using voiceprints.

It’s also the blueprint for another business: Personal subscriptions.

I have written a lot about the qualities that make Amazon a great business, but at its core the company has always been about experimentation. Many firms pay lip service to innovation. Amazon, under the leadership of its founder Jeff Bezos, has always walked the walk. The Seattle, Wash.-based company routinely takes big risks to build new revenue streams.

Some of these fail spectacularly.

Does anyone remember the time the company tried to sell a smartphone to compete with iPhones? The Fire phone was a colossal disaster, but it didn’t burn the eCommerce giant. If anything, learning from the fast failure made Amazon a stronger, more focused business. The Alexa lineup of cloud-based digital assistant devices rose out of the ashes of Fire phone.

Oddly, Halo shares no DNA with Alexa. The activity band has a heart rate monitor and sensors to collect activity, sleep and voice data. However, audio inputs are never sent to the cloud. Everything is processed on your Bluetooth paired smartphone. Amazon product managers say Halo’s software can determine a person’s emotional tone by grabbing small voice samples throughout the day.

The 3D body scanning gets mostly the same privacy treatment. The digital information is briefly stored in the cloud for processing, then deleted within 12 hours.

3D body scanning is popular among professional athletes. It’s the best way to calculate body fat percentage, a much better determination of overall health than generic measures like weight, or even body mass index, a metric that also accounts for height.

Halo’s 3D body scan uses the camera on your smartphone, then artificial intelligence and machine learning to make sense of imagery. The application lets Halo wearers see what their bodies will look like if they keep up a healthy diet and exercise. Presumably, this personalized experience will also improve over time to motivate subscribers to renew.

The last part is key. This is a $3.99 per month subscription service. Ultimately it could be an important new source of revenues, but first the company needs to sell units.

A Consumer Intelligence Research Partners report in 2019, estimated that 62% of American households held Prime memberships. These loyal shoppers were instrumental to the success of Alexa.

In the fall of 2014, smart speakers did not exist, and nobody expected one from Amazon. Six years later Alexa-enabled devices have sold 100 million units, and are at the center of the smart home ecosystem, with 70% market share.

Halo has the potential to dwarf Alexa. Overall sales will be goosed by ongoing subscription revenues. And to entice buyers to keep renewing, Amazon is partnering with third parties to add value.

Initially, the company is working with WW, formerly Weight Watchers ( (WTW) - Get Weight Watchers International, Inc. Report). Subscribers can choose to have their data shared with WW to automatically update their WW points. Other collaborations with the Mayo Clinic, Exhale, Aaptiv, Lifesum and Headspace are developing, according to a story at the Verge.

If the subscription lapses, the band will still perform the basic functions like sleep and activity tracking. However, to get the full benefit of Halo users will have to pay a monthly fee.

It’s clearly way too early to gauge the appeal of Halo, but investors should not lose sight of what it represents. Personal subscriptions is another grand experiment in the spirit of Alexa. It’s a way to get fiercely loyal customers to use and ultimately pay for services on an ongoing basis.

This is different proposition than a Prime membership, that is usually shared within a household.

Amazon shares have had a big runup this year, surging 84% to $3,400. The stock trades at 77x forward earnings and 5.3x sales. While that is on the upper end of valuations for eCommerce companies, Amazon remains attractive for the ability of managers to build new revenue streams.

Halo could be a big, new business.

Buy the stock into any short-term weakness ahead.