Jawbone is introducing two new fitness activity trackers, including its next-generation UP3 wristband wearable that will one day know when you’re dehydrated, stressed and fatigued.

Sleek in design and significantly smaller than its previous UP24 model — check out the picture above for the difference in size — the UP3 ($179) comes with advanced activity features that can differentiate exercises, such as swimming, running and tennis, to better gauge calories. It also includes sleep tracking, which can signify REM, light and deep sleep

Unlike many newer fitness tracker models, Jawbone decided not to incorporate a display or smartwatch-like notification features that are popping up on competitors such as the Fitbit Charge HR and the Microsoft Band. Instead, you can tap the top of the device to see lights that indicate how close you are to your daily goal. More data is displayed on the corresponding app.

“Many people don’t want to wear a device with a screen that lights up when they get a call or message — and if they do, they know they can get a smartwatch,” a Jawbone spokesperson told Mashable. “We believe that fitness trackers should be discreet, not interrupt your day and shouldn’t be a clunky piece of cheap plastic, and that is what we’re up against in the market.”

By keeping the device display-free, the Jawbone UP3 remains sleek and looks more like a piece of jewelry than a mini-computer wrapped around the wrist.

“There are some beautiful smartwatches coming out soon — and Jawbone software will be a part of it — but we still believe there is a place for a fitness-focused wearable, too,” the spokesperson said.

The device has a watch-style clasp that adjusts the size of the band and holds it in place. The battery life is pretty solid too, promising up to seven days of tracking in one charge. The UP3 can also be dunked in water up to 10 meters deep.

The UP app software is getting a refresh too: Whether you purchase a new model or use an existing one, a new feature called Smart Coach gives personalized guidance to reach your goals. The more data the device collects (sleep, steps taken, meals and so on), the more tailored the suggestions will be.

The UP3 also monitors your resting heart rate first thing every morning. By eating better and staying active, you can see if your heart rate count goes down — an indication of how healthy your heart is, before daily stresses and caffeine kick in and bump it up a few notches. Eventually, the UP3 is expected to offer continuous heart-rate tracking — the technology to do so is already baked in, but will be pushed out in an app update in the future.

Along these lines, perhaps the neatest part of UP3 is what is yet to come: It is set to eventually tell you when you’re dehydrated, fatigued or even stressed. Those features will be powered by built-in bioimpedance and skin/ambient temperature sensors. Bioimpedence sensors measure your body’s composition and provide a more complete understanding of your health.

Although Jawbone didn’t say when a software update will be available— the timeline is for “later this year” —it’s already in the works. We’re assuming it will be right in time for the holiday shopping season.

The UP3 comes in three colors: black, red and silver.

The company also revealed the UP Move ($49.99), an activity tracker that can be clipped to clothing or snapped into a wristband-like accessory. The small gadget, equipped with tiny sensors, will track steps, calories and workouts, as well as your sleep cycle. It works with the UP App and can get tips and feedback from the Smart Coach, too.

The UP Move, which can last up to six months on one charge, is billed as a low-cost tracker for those who might be new to wearables. The UP Move will ship later this week.

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