With so many fitness wristband trackers on the market, it's nearly impossible these days to find one that doesn't track steps, calories, distance and your sleep cycle. Companies are moving beyond the basics to add new features and incentives to stand out among the onset of others.
Perhaps the most popular wristband trackers come from companies like Jawbone, Nike and Fitbit, but the category grew even bigger at this year's 2014 International CES in Las Vegas with product announcements from big brands such as LG and Garmin and startups like Jaybird. While many of the new devices ship later this year, Jawbone is still settling into its latest version: the Jawbone UP24, which debuted in November.

The Jawbone UP24 has a lot going for it: it's the sleekest wristband tracker on the market, with a slim form factor that's appealing for both men and women. Trackers have developed a reputation for being rugged and masculine — not something you'd want to keep on for a fancy dinner — but the UP24, much like its predecessors, is styish. It can blend into both work and nighttime attire much easier than the rest. It comes in black (oynx) and orange (persimmon) and in three sizes (small, medium and large). The price is $149, or $20 more than the original Jawbone UP, which is still available for purchase.

The new model is the first Jawbone tracker to go wireless, allowing you to sync your data to the app via Bluetooth, much like how the Nike+ Fuelband and Fitbit trackers work. Although that alone makes the UP24 is an improvement over previous iterations, there's still significant room for improvement. It lacks a screen, for starters, and it can easily fall off the wrist. Notifications are unreliable. The UP24 may be easy on the eyes and it's still a highly productive wristband tracker, but you'll have to be more self-disciplined with referencing the app to get the most out of it.
Similar to the previous UP, the design is slim and features a comfortable rubber texture. It slides easily onto the wrists, but sometimes falls off — at times, I noticed my UP24 missing entirely. While the Nike+ Fuelband SE and the Fitbit Force locks around your wrist, the Jawbone snakes around without a clasp.

And unlike the Fuelband SE and Force, it doesn't include a screen. The Fitbit Force (pictured below, right) is one of the only wristband trackers to feature an OLED display, which doesn't drain the battery as quickly as the Fuelband's LCD screen. Sure, the UP24 looks more like jewelry without either, but it means your only window into the data the band collects is the accompanying app.

It's easy to forget why you're wearing the Jawbone — both the Fuelband and Force serve as constant reminders (and positive reinforcement) when you touch the screen and it reveals key data about your daily activity. The UP24 just sits there until you pick up your smartphone, open the app, transfer the data and analyze the information.

One improvement over the earlier UP is the redesigned button on the edge of one end. It takes up less real estate than before and is less likely to get stuck on clothing.
The UP's battery is rated to last seven days — the same promised amount as the original UP. Charging the device takes more effort than most, since you need to remove the cap on the end and hook it into the accompanying dongle, which then goes into the USB port of your compute or charging plug. By comparison, the Nike+ Fuelband SE wins with its charging approach: it plugs right into your computer's USB port without the need for a dongle or cord (see picture below).

Image: Mashable image base

By popping the small button near the band's Nike+ logo, the band unhinges and the USB connector appears, the same as its done with other Fuelband models. You may try to snap the UP24's connector into your mobile device or computer (after removing the cap), but instead, it snaps into a dongle, which is then used for charging.
It's important to note that the Jawbone UP24 is not waterproof, and is possibly less waterproof than the previous UP. Tech Editor Pete Pachal wore his UP24 in the shower every day and it stopped working after about two weeks, whereas he did the same with the UP and it kept on ticking (the instructions specifically say to take it off while bathing).
Meanwhile, I often forgot to put the device back on after showering, so a waterproof solution (possibly similar to Sony's smartphones) would be in the best interest of any company wanting to keep the device fully functioning and consistently on each user's wrist.
The UP24 is at the top of its game in terms how the software looks, its ease of navigation and sleep-tracking capabilities. Jawbone's revamped app (version 3.0) is easy to figure out and fun to use. It details how long you've slept — light sleep vs. deep sleep — how many times you woke up and how quickly you dozed off. You can even program a "smart alarm" that wakes you at the optimal moment during light sleep, so you feel more refreshed and less groggy.

New to the UP24 is a sleep-recovery feature for nights you forget to manually push the device's button to start sleep-tracking mode. The device looks at data from the night before and lets you manually enter your sleep and wake times. It's not as accurate as monitoring your full cycle, but logging the information is still important for pattern monitoring.
It also shares sleep-tracking data with friends (if you want it to) as well as how many steps you've walked in a day. Not only does this add a gamification factor, it makes it fully social: you can compete against friends and leave comments along the way (think: smack talk or words of encouragement). You can also set daily goals via the app, including what time you want to get into bed to how much water you want to drink. It lets you know when you've hit those goals and gives you nudges along the way.
However, one of the biggest setbacks for the Jawbone UP24 is the buggy nature of its push notifications, which are supposed to keep users on top of their progress. While testing the Jawbone UP, I never received a single notification or email about my progress, nor did my editor (before his stopped working in the shower). We initially thought this was because of the way we tested the app (via TestFlight), but even after starting from scratch, the notifications never game. Others have complained about not receiving notifications via online message boards, so the issue was not unique to our testing.
The lack of notifications is serious problem, since Jawbone touts them as one of the UP24's features. Their usefulness isn't just a gimmick, either — since syncing is now automatic and not manual, notifications become the primary way you engage with the data you're accumulating. The concept is a smart one, as long as it works, and it didn't for us and others. Without notifications, the UP24 is a crippled product.
Jawbone made this statement after we repeatedly tried and failed to fix the problem after consulting with them:
"Notifications are working as designed for most users, but in circumstances where a user isn't getting a notification as expected, it could be because of individual configurations, like having your Bluetooth turned off, notifications turned off, or due to iOS closing the app while it runs in the background. Or, it could be that you've already seen the data, or that a goal isn't likely achievable so it would feel like UP is nagging you by sending a notification."
At $149.99, the Jawbone UP24 costs more than the Fitbit Force ($129.99) and the same as the Nike+ Fuelband SE ($149), but you'd be better off with one of those devices, unless you're dedicated enough to check the app throughout the day. The UP24's lack of screen makes it visually appealing, but cuts down on the overall experience. Plus, its unreliable push notifications make it a risky purchase.
What's Good
Sleek design
Sleep tracking
Beautiful software
The Bad
No screen
Slides off wrists
Unreliable notifications
Bottom Line
The Jawbone UP24 is great for anyone into who wants to look closer at their "quantified self," making adjustments to their sleep and other activities to live better, although its lack of screen and buggy software put it a step behind the rest.
Images: Mashable, Christina Ascani