New Jawbone tracker takes your heart rate

jawbone fitness tracker

The newest fitness tracker from Jawbone has the ability to measure your heart rate on demand, tell if you're dehydrated, take your temperature, and detect if you're stressed or tired.

Unfortunately, it can't do all those things right now.

Jawbone is adding two new fitness trackers to its lineup, including the new $179 Jawbone UP 3 wristband. But instead of waiting until all the features are ready to go, Jawbone is pushing the UP out in time for the holiday season (specific release date TBD). That means some of the more intriguing capabilities won't be added until a software update sometime next year.

The device's key new ingredient is something called a bioimpedance sensor. Most wearable fitness trackers use an optical heart rate sensor that flashes a light onto the skin to see blood flow and capillaries. The hardware can be bulky, which is why many entry-level fitness trackers don't do heart rates.

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According to Jawbone, its bioimpedance sensor detects the physical resistance of body tissue to get more accurate readings for a wider range of metrics. For example, if you have more salt or liquid in your body, that slows down the resistance.

Out of the box, the $179 UP 3 will automatically read your resting heart rate. It will track sleep cycles and know when you're working out, in addition to the usual step and activity tracking.

Jawbone's other new product is the UP Move, a small $50 modular fitness and sleep tracker aimed at wooing the many first timers who aren't counting their steps yet.

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After years of success with audio devices, the company branched into consumer wearables in 2011 with the first Jawbone UP. Unfortunately, there were massive product failures, most notably bricking (when a device shuts down and can't be restarted). The CEO issued a public apology and offered full refunds to unhappy customers.

A year later, Jawbone released a far better version of UP, going up against competitors Nike and Fitbit. Now every company seems to be working on a wearable of some sort, whether it's a hardcore fitness gadget or high-end smart watch. Jawbone is focusing on lifestyle devices that people wear 24 hours a day. That means they can't be too big, too power hungry, or too unfashionable.

To stay competitive, Jawbone needed to bring something fresh to the wearables party. In 2013, Jawbone acquired wearable fitness company BodyMedia for more than $100 million. Some of that technology is in the new UP 3.

The power that technology adds to the UP could be a huge hit for Jawbone. When it actually makes it to consumers' wrists.

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