Jawbone UP3 Review - Flawed Ambition

There's a war on, and it's for space on your wrist. For years it's been fitness trackers like Jawbone's new UP3 that have been sneering at traditional watches, but as smartwatches like Apple Watch mature, now it's the health bands that are under threat. Like any good – or cruel – personal trainer would tell you, when you feel the burn it's time to push harder, and so Jawbone hasn't held back on the tech for its latest flagship. So many sensors, but does UP3 make sense?

Jawbone's previous UP bands were springy rubber loops, hooking around your wrist like a kid's toy. It meant they were easy to put on, but it also forced Jawbone to offer different sizes.

UP3 hits reset, with a completely new design that, though recognizably from Jawbone's stable, is more flexible in how it fits. A metal clasp slides along one of the hypoallergenic silicone straps, with a hook on the other strap clipping into place. Unlike a watch strap, there are no holes to line up, which in theory means infinite adjustment possibilities.

Unfortunately the practicality suggests there's still a good reason why watches haven't migrated to a system like Jawbone's. It's not uncommon to find that the UP3's clasp has loosened over the course of the day, requiring some minor adjustment, or if you've been tossing and turning overnight to wake up with the strap more stretched out than before.

It's rain, splash, sweat, and shower-resistant, but despite Jawbone's initial efforts you can't wear UP3 while swimming.

Meanwhile, though the band overall may be lower in volume than the UP24, that doesn't necessarily make it more comfortable. Where the previous design was entirely encased in rubber apart from the end-caps, the UP3's main section is hard plastic. I particularly struggled to get comfortable while trying to sleep, finding the body of the wearable would dig into my wrist, though your mileage will obviously depend on what position you sleep in.

UP24 was controlled by a single button built into one end of the strap. Easy to find with a finger, but it had sharp edges that could scratch you, and was a little too prone to being inadvertently pressed.

For UP3, Jawbone has switched altogether. Now, the button is a touch-sensor in the fascia, with LED indicator lights to show whether you're set to day or sleep modes. In theory, a quick double-tap on the top rouses the wearable into showing what mode it's in, and a long-press switches between them.

I saw "in theory"; in practice, this has been the most frustrating part of the UP3 experience. At times I double-tapped, and double-tapped, and double-tapped some more, the band resolutely refusing to wake up. It's particularly annoying when all you want to do is settle down and go to sleep, and yet the UP3 doesn't want to let you flick it into sleep mode.

Jawbone told me it didn't want to make the system too prone to triggering because you're only going to use it once a day. My counter-argument is that, if this is a) the only control, and b) the primary way you interact with the hardware on a daily basis, then it's one thing you need to get spot on.

Things did get somewhat better once Jawbone swapped out my original grey UP3 – the initial round of hardware seeded to press was preproduction – for a black, production version, though it's still not a sure thing that the band will spot when I'm tapping.

What most differentiates UP3 from the rest of Jawbone's range is the row of five gold bioimpedance sensors running around the inside of the band. They're not just an alternative to the optical heart rate trackers we've seen on rival devices like Microsoft's Band and various smartwatches; according to Jawbone, the clever thing about UP3 is that its sensors can be reprogrammed over time to measure different things.

In theory, it could track your galvanic skin response, your respiratory rate, and your hydration rate, and thus figure out factors like how much water is in your body and even how physiologically stressed you are.

I say theory, because out of the box UP3 only uses the sensor for one thing: heart rate monitoring. It even does that in a comparatively controlled way, too, taking what amounts to a single reading every day.

Jawbone's premise is that of all the heart health measurements you could gather, the most telling is resting heart rate (RHR). That is to say, the speed your heart is beating at before the stresses of your regular life take their toll, best gathered in the moments as you wake up.

So, when in sleep mode, UP3 keeps an eye on your pulse and then figures out your RHR from just when you start to surface. The three cups of coffee you chug before you leave for work won't affect it, and neither will the twenty minutes of hurried yoga you do: it is, Jawbone claims, the most accurate way to figure out what your body is doing.

Clever stuff, but there are undoubtedly times when it would be nice to also see quite how fast your heart is racing (or otherwise) during the remainder of the day. While exercising, for instance, or just prior to an interview. That's going to be different to RHR – it would of course be impossible to actively check your resting heart rate – but no less valuable as a body metric.

Right now, though, it's not possible. Meanwhile, I also encountered a few issues getting a consistent reading, for a start because it relies on the sensors being in adequate contact with your skin.

Strangely, a couple of nights UP3 had clearly been tracking my pulse (it uses the sensors to help gage sleep phases, too) but didn't come up with a final RHR reading. I experimented with the fit – trying to accommodate the vagaries of the clasp with comfort, having woken up a couple of times with a row of square dints impressed into my wrist – and ended up missing a few days readings as a result.

Even if Jawbone isn't going to tell you your heart rate at any other time, it could at least give you some sort of "that's tight enough" feedback so you know you're wearing it right.

Jawbone's software and the background data crunching it does have always been my favorite part of the UP experience. Plenty of fitness wearables are happy to tally up your steps and give you a number or a graph, but very few of them do as solid a job as putting those metrics into context as Jawbone does.

As you might expect, those same core strengths are carried over for UP3. Walk through your normal day and it'll track how many steps you've taken, the distance traveled, and how many calories you've burned. Do something a little more strenuous, and the app pops up a notification asking for confirmation that you were exercising, and then to define what that exercise actually was.

Meanwhile, the Smart Coach begins to try to coax you into a healthier lifestyle. If you're short on steps compared to your typical day, the UP app will pop up a suggestion to get moving; if your bedtime has been irregular, it'll prompt you to get your head down at a more sensible time.

Jawbone turns those improvements into little games, setting challenges and then – if, Mission: Impossible style, you accept them – reminding you later to follow through on your commitment. Successes are marked with reward cards in your timeline, and can be shared on Facebook or Twitter so that everybody knows you were tucked up in bed by 10:30pm.

If you want, you can dig into food logging, though I've found my particular diet doesn't necessarily jive with Jawbone's default idea of what sort of eating is best. I was more interested in how UP3's extra heart rate and sleep metrics would be combined, though the answer is only partway satisfying.

On sleep, the new sensors now add REM phase detection to the previous "light" and "deep" measurements older UP models could track.

REM is, in effect, when your mind is recharging whereas deep is when your body gets its turn, so it's certainly useful to see a more comprehensive breakdown of how much of each you got.

Unfortunately, beyond totaling up the time, the UP app hasn't really given me any extra insights. I get praise for hitting an 8hr sleep goal and warned I may need a brisk walk to rouse me on days I miss it, but I was getting those already without the REM factor.

Resting Heart Rate can be similarly mysterious. On the times it went lower than the 30-day average, the UP app would praise me for having exercised, slept, and eaten "mindfully", or suggest that the change was "probably" down to living healthier.

Considering the UP3 was already tracking two of those three metrics – sure, I'd skipped food logging but it knew when I was sleeping and it knew when I'd exercised – I'd have liked to have seen some greater insights. As it stands, while I know a lower HRH score is considered "good", and am invariably pleased when I'm told I've achieved one, I'm not entirely sure what I'm doing to make that happen.

That means it's difficult to do it again, and consistently.

The rivalry for a spot on your arm has never been fiercer. On the one side, Jawbone faces a challenge from other fitness-centric wearables, such as from Fitbit or Microsoft's Band. They often support anytime-measuring of heart rate, such as during specific workouts. Microsoft's is probably the most complex, with its integrated touchscreen that can walk your through exercise routines, but it's huge and bulky, and I found it a real pain to wear while sleeping.

On the flip side are the smartwatches. Most of the Android Wear options can track at least steps and probably heart rate, too, and Apple Watch does a surprisingly good job not only of gathering metrics but nudging you into the little behavioral changes that add up over time.

Jawbone's biggest advantage over the watches, however, is battery life. It'll last up to seven days, whereas neither Apple Watch nor any of the Android Wear crop will manage that. It charges quickly, too, going from flat to full in less than two hours, though the new magnetic USB charger dongle only clips on in one orientation and can be a little fiddly.

Ironically, it may be Jawbone itself that eclipses the UP3. The company's app already works with third-party fitness metrics pulled in through things like Apple HealthKit, and in the pipeline is an update that will run on Apple Watch itself, just as it has now for Android Wear, Pebble, and other platforms. Then you don't need an UP3 at all.

Jawbone is ambitious, and I admire that. Throwing a me-too heart rate sensor into its new UP and adding just one more metric into its app would've been the easiest option; instead, it picked a more complicated technology with far more potential.

Unfortunately, right now that potential is all a little vague – Jawbone has no public roadmap for when other metrics might be enabled – and what UP3 does today falls short of what I've come to expect from the company's generally great software. Knowing REM sleep and resting heart rate is interesting, but it's lacking in context. I want more than just extra colors on the graph.

Jawbone's track record at progressively improving its software and analytics leaves me hopeful that over time UP3's abilities will be better reflected in its companion app. $179.99, though, is a big vote of confidence to expect someone to make, especially when the UP2 – which effectively redresses the UP24 with the new styling – gathers the core data that's currently best analyzed, and for just $99.99.