Time to Flex: We check out Fitbit's new wristband tracker

Credit: Alice Truong/DVICE

Fitbit is one of the most recognizable names in the health tracking space, but it's playing catch up when it comes to wristband monitors. Today, the company best known for its activity and sleep monitors that clip onto clothes has officially launched Flex to take on the likes of the Jawbone Up, Nike Fuelband, and Larklife, among others.

After testing the band for the last week and a half, we've determined that while Flex isn't the most feature-filled tracker, it's certainly the most convenient. With wireless syncing, it provides the most seamless experience among tracking bands today.


The heart of Flex is a small removable tracker that lives in a silicon band. It has largely the same capabilities as the Fitbit One, including tracking steps walked, distance traveled, floors climbed, and sleep quality.

The removable design is a smart one, avoiding the Jawbone Up's initial pitfalls. Because electronic components are spread throughout the entirety of Jawbone's band, a number of its initial units from the fall of 2011 bricked. After refunding all users, not just the affected ones, the company went back to work to create a band rugged enough to endure water, extreme temperatures and occasional fiddling. To design a band that's too delicate is to intentionally design an unwieldy user experience. (I, myself, have experienced issues, with two bands malfunctioning within the first six months of the Up's reboot.)

Two bands (one large, one small) are included with Flex. The latching mechanism takes some getting used to, requiring more force than I expect to secure around my wrist. Though there are notches, there's less flexibility in sizing. Whereas the Up molded to the size of my wrist over time, the tightest adjustment on Flex's smaller band (the only one I received with my review unit) was still about an inch too large for my wrist. It's loose but not to the point where it'd fall off.

Noticeably missing in Flex is an LED display that provides immediate feedback on the day's progress. This was one of my biggest gripes with Up, since the hardware was essentially useless without the app. Fitbit compensates for the lack of screen with five LED indicators, each one representing 20 percent progress toward the day's step goal. When the goal is met, all five light up and the band vibrates to mark the occasion. Without a screen, I also miss being able to see the time or how much time has elapsed in stopwatch mode. Furthermore, Fitbit's personality is also muted without a display. I enjoyed the occasional spunky encouragement I received from the One, which included: BURN IT, NO DONUT and STEP GEEK.

Seamless experience

As an all-day tracker, Fitbit is water-resistant, so it can be worn while swimming, washing dishes, or showering. Having it on me at all times means no longer suffering from I-just-did-an-amazing-hike-but-forgot-my-Fitbit remorse.

The One is also considered an all-day tracker, but I never switched out of day mode when I wasn't testing the device. It required removing the tracker from its clip holder and placing it in a wristband (and vice versa in the morning). With Flex, switching between modes means tapping on the tracker four or five times quickly. It will vibrate and flash two LEDs to indicate it's tracking sleep. The same gesture also tracks activities.

The insight into sleep isn't the most robust, giving me duration and times awakened. In contrast, Up breaks this information down to deep and light sleep. Of course, neither of these quite compare with Zeo, a head-worn strap that measures brain waves, charting the course of the night into four states (wake, REM, light sleep and deep sleep). But using it was uncomfortable, and lately, there's chatter that Zeo is going out of business.

The other nice sleep feature is the silent alarm, which will gently vibrate you awake in the morning. However, Flex's alarm goes off at a set time, whereas Up will do so at the optimal point in your sleep cycle within a set window of time. In general, Up uses vibrating notifications that seem much smarter than Flex. A power nap mode will calculate an optimal nap time (typically half an hour to 45 minutes) and vibrate you awake, and there's also an idle alert that will nudge you if you've been inactive for a while.

By far, the best feature of Flex is wireless syncing. With compatible smartphones and tablets (newer iOS devices as well as the Samsung Galaxy S III and Note II), Flex uses Bluetooth 4.0 to update periodically while the app is running in the background. With a USB dongle, it also syncs effortlessly on a computer when Flex is within 15 feet. No need to detach, reattach, plug in or any of the such.

Covering bases

Because an iPhone screen isn't always the best way to present so much data, Fitbit also has a very comprehensive health portal. The company is beta testing a new responsive personalized dashboard that looks very promising, displaying in customizable tiles only the information you care about. For me, that's my activity, friends' average step count and sleep quality, less so calorie logging.

Broadening into bands is a way to capture market share among fitness-minded techies. James Park, CEO and co-founder of Fitbit, had admitted as much back at CES. Alone, Flex is a perfectly fine tracker for the everyday consumer, but the data that's provided can be superficial compared with other fitness trackers. Still, for $100, it offers a lot and even has an advantage: wireless syncing. Seamlessness is Fitbit's leg up on the market, and we have that with an all-day wristband that syncs wirelessly in the background with mobile devices. It's perfect for those who want their gadgets to work for them, not the other way around.

(All images Alice Truong for DVICE.)

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