Fitness trackers are an important part of everyday life for those interested in improving their health. The UP3 is Jawbone's latest wrist-worn venture and it promises all the bells and whistles that top technology can offer while boasting a sleek new design. The UP3 vows to improve your wellness by providing you with quality data about your every waking and sleeping moment. 

Jawbone's first tracker devices were stiff, bulky and difficult to incorporate with clothing other than workout gear. Although the UP3 will not be mistaken for designer jewelry, its sleek, slim design is akin to a minimalistic wrist band. Jawbone made a strong effort to make this model as small and light as possible, so that it can accompany other jewelry or smart devices on your wrist stylishly. The UP3 boasts “one size fits most” technology and is more comfortable than previous models. This time, Jawbone opted to offer only two colors, black and silver, instead of their usual wide range of color choices.

The UP3 features a new watch-like, adjustable hook-and-eye clasp system instead of the crossed arms that earlier models offered. The device is thin and comfortable enough that you can work on your computer without having to remove it. The simply-designed UP3 has a stiff portion that fits snugly on top of your wrist and the rest feels like a flexible rubber band. We found it awkward to try on the tracker, as ideally, the device should be tight enough on your wrist so that the sensors are flush against your skin. You can fasten it by inserting the rectangular metal piece on the band into the clasp which you slide up and down to help it fit your wrist perfectly. Once the UP3 is on, it (seems) to hold on tight. Upon wearing the device, we noticed that the buckle became unclasped on its own. This happened several times, even when the band was pulled tight on the wrist. This is a major issue, since when the sensors are not pressed against the skin, the tracker does not work. 

While the UP3 is durable, it is not entirely waterproof as Jawbone initially intended it to be. Due to manufacturing complications, Jawbone managed to make the UP3 “water-resistant” instead. It is safe to say that the Up3 can accompany you to the shower; however, it must sit on the sidelines while you do laps in the pool. Jawbone's latest device also no longer features a button to switch between modes. Alternatively, you need to tap and “long press” the touch-sensitive face of the tracker to shift between “activity” and “sleep” modes. This feature was a bit difficult to work and made us wonder why this was not an automatic function. Three stylish LEDs on top of the tracker tell you the mode you are currently in; however, there is no built-in display beyond this.

The UP3's defining feature that differentiates it from all other fitness trackers is its ability to read your resting heart rate by using small currents it delivers through the metal contacts against your skin. Your RHR is a great fitness indicator as it measures the point where your heart pumps the least blood. Armed with a tri-axis accelerometer and bio-impedance sensors, the Up3 calculates your RHR while you sleep, either during the night or when you nap. However, you cannot use the heart rate monitor for on-demand heart rate measurement. To us, it seemed to have issues with reading your RHR consistently, as it gave very different readings throughout several nights. 

You can also use the UP3 to track your daily steps, add new workouts, track your sleep, measure your ambient temperature, respiration rate and monitor your food intake. The UP3 offers motivation to push you towards your goals, such as cheerful vibrations upon reaching your step goal. The UP3 also provides observations about workouts and water intake and makes suggestions on how to work towards your fitness goals instead of forcing you to analyze the data yourself. The issue with the UP3 is that you need to understand what to actually do with some of the data that the tracker provides you with and how to apply it to your wellness. Jawbone has made efforts to explain the data to its users though  - for example, it will tell you when you have had prolonged periods of inactivity. This information is much more beneficial than simply having an empty workout log or a recorded number of daily steps. The recommendations are far from perfect and could cross-reference more data, such as pointing out correlations between food intake and activity levels on given days. While at the moment, the UP3 proposes ideas to improve REM sleep, perhaps in the future it could further personalize the advice. 

The tracker also calculates whether you are getting the suitable amount of deep sleep at night and measures REM, light and deep sleep phases. We love the UP3's Smart Alarm feature, which buzzes to wake you at the optimum moment in your sleep cycle. But if the band should fall off or slip so that it is not pressed against your wrist, then it not only will not record your sleep but also, the alarm will not wake you. To exit sleep mode, simply get out of bed and start moving to prompt the tracker to exit sleep mode.

The battery lasts about 7-8 days, but we did not like that it didn't warn us before it was out of battery power. Another negative feature is the design of the charger, which is a magnetic bond placed on the back of the tracker controls. If the tracker is not placed in the exact correct position to charge, then it simply will not charge. 

The UP3's mobile app wirelessly syncs to the band via Bluetooth and is perfect for measuring simple things like counting steps, as it doesn't overwhelm you with data and makes it easy to see if you are accomplishing your goals. Jawbone uses the app to shoot some helpful factoids your way, such as new ideas on how improve your REM sleep. We liked that the app works like a fitness blog that actively communicates with you. The app is available for most platforms and connects to a large number of different devices. This app demonstrates that Jawbone is a great hub for fitness data and works well.

However, we found it a bit too complicated to log some simple things, such as water intake (4 taps and 2 confirmations). The UP3 also does not have a wide range of workout modes to switch through on the hardware, but you are able to record various activities on the app. The UP3 promises to recognize a wide range of activities too, like running, walking, playing basketball, etc. It then prompts you to record the data in the app, which makes logging additional activities quite straightforward with minimal fuss.

It will be challenging for Jawbone to sell the pricey UP3 to a first-time user of fitness trackers, as competitors are offering products with nearly identical features. Still, when compared to simpler products, the UP3 delivers high-quality insights and a comprehensive app that make it genuinely beneficial to improving the user's health. While the UP app may not be as “smart” as Jawbone promises, it's still light years ahead of rival apps that only provide data. If you are looking for a method to get a thorough overview of your health data and workouts, the UP3 is the tracker for you. We look forward to Jawbone offering a fitness tracker in the future that can read your heart rate on-demand, but that's not reason enough to disregard the UP3 at this time.