Sona is a fashion forward activity tracker with serious sensor tech

Variable heart rate sensing and breathing training takes aim at stress
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New York City based smart jewellery company Caeden has unveiled Sona a new connected bracelet a built-in heart rate sensor. The company claims it can measures 10 times more information than a standard HR tracker.

It's designed to look good on your wrist no matter what you are wearing, and features technology to help you learn how to balance life, not just get fit. It is now available for pre-order from the company's website for $199.

We sat down with Caeden's president and CEO, Nora Levinson, for a demonstration of what makes the smart bracelet so special.

The Sona activity-tracking bracelet is a simple leather band that comes in either black or white, with an elegant clasp, available in gold, rose gold, or gunmetal grey. Under the clasp lies the brain of the device, which includes a three-axis accelerometer and a very fancy heart rate monitor.

The most important feature of the Sona is that it's designed to track the variability between the beats of your ticket, marking the exact timing of each heartbeat. And Levinson says the new metrics make a big difference:

"When you get a level of signal accuracy that high, you are able to do some detailed analysis of your underlying autonomic nervous system," she said.

Sona is a fashion forward activity tracker with serious sensor tech

Levinson went on to explain that we have two different branches in our subconscious nervous system, stress response and rest and calmness response. The heart rate variable sensor can provide a metric that allows its user to monitor overall health and wellbeing, not just steps or calories.

The idea is that the Sona helps to develop a well-balanced lifestyle and manage stress at the same time. It will let you know when you are overworking your body, whether through too much exercise, not enough sleep, or too much stress.

"If your heart rate variability is higher, that's better. It means you are well rested and don't have a high amount of stress or you are not over-training," Levinson said.

"Whereas, a low heart rate variability means that you aren't sleeping enough, have chronic stress, are working out too vigorously and your body can't recover."

Sona is a fashion forward activity tracker with serious sensor tech

So, the Sona can track your day-to-day wellbeing, but once you know about it, then what? That's where the app comes in. Caeden, in collaboration with a group of scientists, has developed five guided breathing sessions. Breathing programs are based on different needs, like preparing for a meeting, relaxing before bedtime, etc.

The breathing sessions, called Resonance, helps the user control their heart rate patterns by breathing at a specific speed.

"This is a scientifically built program where, you do this pace breathing at your body's resonant frequency to put your heart rate into a sine wave pattern," said Levinson. "Which increases oxygen intake and helps balance the two sides of the autonomic nervous system."

There is a pulsing icon on the centre of the screen that shows when the user should breath in or breath out. This information is based specifically on the person's heart rate variable. It is not a general breathing trainer, which is why the Sona tracker works exclusively with this program.

Sona is a fashion forward activity tracker with serious sensor tech

We tested the Resonance breathing training with the Sona on. It is surprisingly harder than you'd think to pace your breathing with the app's suggestion. However, after just a few minutes, it became easier and our breathing started to sync up with the target pattern.

The Sona does include typical activity tracking information, like a step counter, how many calories you've burned, and distance you've moved. However, Levinson clarified that the focus is on heart rate variable tracking, including during exercise. Since the sensor gathers detailed heart rate information, the type of exercise you are doing doesn't really matter.

It takes into account how your body responds to activity throughout the day. You don't have to let the tracker know that you are starting to exercise. Since it is always monitoring your heart rate, it will automatically note your active time (when you are exercising), whether you are doing Yoga, running, rowing, dancing, or whatever.

If you don't want to get the classy looking leather band covered in sweat, preorders come with an interchangeable silicone band in black or white so you can switch over to workout wear with a quick change.

In addition to being an activity tracker, the Sona features notification alerts. When you receive a text message or call on your smartphone, you'll get a vibration on your wrist. So, even if your smartphone is in your bag, you won't miss an important communication.

Sona is a fashion forward activity tracker with serious sensor tech

The tech bracelet runs on an 80 mAh rechargeable battery that the company claims can last up to four days with regular use (roughly 20 minutes of Resonance breathing training plus 30 minutes of Active Time monitoring). It connects to a contact-based cable.

Caeden has plans to launch additional straps next spring and will likely look into collaborations with third-party designers for future models. There are also plans to add sleep tracking to the app in the future, which is based on a study being conducted at Duke University that uses heart rate monitoring rather than movement tracking.

Shipping of the Sona is expected in April 2016.

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Lory is a freelance technology writer, who specializes in apps and games. She now works as a contract editor for Apple.

Lory has written for iMore, Lilliput Computing and

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