The Jawbone UP fitness wristband has a lot going for it: It's stylish, durable and comfortable, but it lacks something other fitness trackers like the Nike+ Fuelband SE have: wireless syncing. That changes today with the launch of UP24, a new model that relays your data to the app via Bluetooth. Jawbone's also releasing version 3.0 of the app at the same time as the new UP.
The UP24 looks pretty much exactly same as the regular UP — both are flexible bands that wrap around your wrist with a cap on one end and a button on the other. The only external difference: The button is redesigned since the old one would sometimes get caught on edges or pieces of clothing. Now it's smoother, with barely and separation between the button and the rubber portion.
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Remarkably, the UP24 gets the same seven days of battery life as the UP thanks to Bluetooth Smart technology (aka Bluetooth 4.0 or LE). There's an important difference between the models, though: The UP24 costs $149, or $20 more than the original UP, which is still available.
So why did it take so long for Jawbone — whose roots are in wireless accessories — to offer a Bluetooth option?
"Our decision to keep it out of the first version was deliberate," says Travis Bogard, vice president of product management and strategy for Jawbone. "Bluetooth Smart is at a point where it's in enough phones. We think it's ready, and we were able to think about it not just the syncing but how do we use this to as a platform to deliver a different experience."
Wireless syncing changes the UP experience: Since there's no longer a specific time the user needs to sync the device, notifications are much more important. That's helped by Apple's addition of background app refresh in iOS 7, which lets apps run in the background even if you haven't launched them recently. For example, after you wake up, the app can send you a notification telling you how well you slept and for how long.
UP 3.0 also lets you set goals beyond the overall number of steps you take and hours you sleep. Users can now specify one-time "Today I Will" targets, like "Today I will get to bed by 10:30" or "Today I will drink 5 glasses of water." Users will get notifications to nudge them to their goals and congratulations when they achieve them, and the app will even suggest goals based on your habits.
The app upgrade also brings a much-demanded feature: sleep recovery. Both UP bands require the user to manually push the button when they go to bed, and if you forget, your sleep won't be recorded (you could manually enter it later, but it wasn't obvious or easy). Now the app will automatically analyze data from the previous night if you forgot to press the button and let you edit your sleep/wake times. The recovered data won't be as precise as real-time data, but it's better than nothing.
Finally, the new app will recognize streaks and milestones, sending you an "attaboy!" notification whenever one comes up. UP 3.0 will be iOS-only for a time, although the company says it's working on the Android version as well.
"Health is ultimately about taking a lot of small steps to get to where you're trying to go and about tracking that progress over time," says Bogard. "It can be validating and rewarding to celebrate those moments as you make that progress."

The UP24 is available in two colors: black and red. You still charge via a USB connector, which still connects to the band through a minijack connector, although the new model's is a 1/4-inch jack instead of a regular 1/2-inch one to make clear to owners that the jack isn't used for syncing.
I've been wearing the UP24 for a few days. Although how the notifications work with iOS 7 hasn't been as advertised (I haven't received a single notification yet), the wireless syncing works well. As soon as you launch the app, the data syncs without ever needing to remove the band. That's great, but it's supposed to sync in the background, not at launch.
The lack of syncing could be due to a bug in the early build of the app, and we look forward to fully trying out the ecosystem with some of Jawbone's partner apps that make use of the UP platform. Watch for a full review in the coming days.
Images: Mashable, Christina Ascani