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Fitbit Flex 2 review: A low-key, wear-anytime tracker that's swim-proof (at last!)

If all you need are the basics, this is the fitness tracker to get.

Dan Graziano Associate Editor / How To
Dan Graziano is an associate editor for CNET. His work has appeared on BGR, Fox News, Fox Business, and Yahoo News, among other publications. When he isn't tinkering with the latest gadgets and gizmos, he can be found enjoying the sights and sounds of New York City.
Dan Graziano
6 min read

At last, there's a Fitbit that's swim-proof!

The Good

The Flex 2 is slim and swim-proof, can track basic fitness data and supports a variety of accessories, including pendants.

The Bad

It lacks a display and the more advanced features of other Fitbit trackers. Lacks heart rate tracking. The LED lights can be confusing; battery life should be better.

The Bottom Line

The Fitbit Flex 2 doesn't have all of the bells and whistles of other trackers, but it's finally swim-proof, and it does the basics and it does them well.

But in exchange for that long-overdue swim-friendliness, other features are lost. There's no heart rate tracking, and it doesn't have a display. Are you OK with that compromise?

The Flex 2 looks, in many ways, like the perfect slim tracker from Fitbit that we'd wanted for a while: It's like Fitbit's version of the Jawbone Up2. It's $100 (£80 or AU$130 converted) and will begin shipping in early October. It comes with a rubber strap in both large and small sizes, but the beauty of the Flex 2 is its customization.

You can pop out the tracker and pop it into a different color wristband, a metal bangle or even a necklace. It's the most versatile Fitbit, and much like the older Flex, it comes with a variety of fashion-branded accessories from Tory Burch and others. It's an overdue upgrade, and the water resistance and swim racking on the Flex 2 might be reason enough to get it for some.

I do like the Flex 2. It's the tracker to get if you want something that can be both discreet and stylish. It's a sleeker tracker than the bulkier Fitbit Alta released earlier this year. It's priced well. But yes, there are sacrifices to be made.

Swim-proof (finally!)

The Flex 2 is the first Fitbit you can wear in the shower and while swimming. It's waterproof down to 50 meters (about 165 feet) and can be used in both fresh water and salt water. I love not having to take the tracker off when it's time to shower, which also means I'm less likely to forget it on my dresser.

Like the Charge 2, the Flex 2 can also automatically recognize and record workouts. This includes walking, running, biking, aerobic exercise and others. Due to the new swim-proof design, it's also the only Fitbit that can track swimming (you have to enable the feature in the Exercise section of the app) Now that Fitbits are effectively automatic trackers, it's a little easier to swallow the fact that this doesn't have a display.

Sarah Tew/CNET

It's all about accessories

The Flex 2 is 30 percent smaller than its predecessor, the Fitbit Flex. It's slim and discreet, which is what appeals to me, and it could even be worn next to a traditional watch (if you have the wrist room). My only complaint is with the strap. It's secure and never fell off my wrist, but you have to swap out the two-prong connector when switching to a new strap, which was actually pretty difficult.

Besides the two different-sized bands in the box, there are a variety of accessory straps in multiple colors and designs. There are rubber ones, leather ones (coming in 2017 from the designer collections), and gold and silver bangles and pendants. The accessories start at $15 (£10, AU$20) for rubber straps, all the way to $100 (£75, AU$130) for the gold bangle.


The Fitbit Flex 2 tracker and necklace (left) and Misfit Shine tracker and necklace (right).

Sarah Tew/CNET

A quick poll of my female colleagues found that these designs, mainly the pendant, were appealing, especially compared with the nearest fitness-accessory equivalent, the Misfit Shine necklace (pictured above). One colleague complained that the bangle was "lacking pizzazz" and another said the Fitbit pendant was a little "too long," but both liked these options better than the rubber strap.

Everyone agreed that having these accessory options is a good thing. They help keep the Flex 2's design fresh, and help it not feel like a fitness tracker. While some complained about them being too expensive, most agreed they would make nice gifts.

In addition to the bangles and pendants mentioned above, Fitbit said we can expect more luxurious bands from designers Tory Burch, Vera Wang and Public School.

Sarah Tew/CNET

It does the basics (and a little more)

The Flex 2 tracks steps, distance, calories burned, active minutes and sleep. There's no heart rate sensor, and it doesn't measure floors climbed.

There's also no display. Instead of a clock or a screen, the Flex 2 uses vibration and five tiny LED lights to show you how close you are to reaching your daily step goal and alert you to incoming calls and texts. The Flex 2 can serve up get-up-and move reminders just like the Fitbit Alta, the Charge 2 and the Blaze, which makes you walk 250 steps to "win" the hour, but on the Flex 2 these reminders become buzzes and cryptic flashing colored lights. End result: not as motivating, somehow.

Sarah Tew/CNET

The different LED colors were confusing. The bracelet buzzes and flashes blue. Should I get up and move? Oh wait, now it's blinking red. Does that mean I have a text message, or did I just beat my step goal? Most people won't have a decoder ring handy.

In other words, it was easy to forget what each light meant. (For the record, blue means you have a call or text message, red is to get up and move, and all the lights glow when you reach 10,000 steps.)

Battery life could be better

I got about four and a half days of battery life on a full charge when wearing a Flex 2, which isn't great. At Day 3, the app gave me a low battery warning. It died the next day, but I didn't know for almost an hour. There was no vibration, or final warning. I went to sync and nothing happened. That's an easy way to miss out on steps, which is frustrating.

Sarah Tew/CNET

Fitbit claims you should get five days of battery life, which would be fine for a more advanced device, but it should really last longer. There's no display or optical heart-rate sensor, two features that put considerable drain on a battery. And considering how the Flex 2 just drops out without warning on low battery, I'd want to charge mine the moment I got a low battery warning, and not risk it.

I expected the Flex 2 to last a full week or longer. The Jawbone Up2, which was an old favorite of mine, managed to get a week. So do most basic fitness bands without displays.

Charging is also annoying: The Flex 2 comes with yet another proprietary and totally different charger from every other Fitbit. You have to remove the tracker, which is an extremely tiny little stick, and insert it into a small dock. A full charge will take up to 2 hours.

Sarah Tew/CNET

The Fitbit app is still one of the best

There are a lot of fitness trackers out there, some of which are cheaper than the Flex 2, but one of the reasons you buy a Fitbit is for the software. The Fitbit app remains one of our favorites. It's easy to use and is compatible with a lot of third-party apps, such as food-tracking app MyFitnessPal.

If one of your friends owns a fitness tracker, there's a good chance it's a Fitbit. The Fitbit app has the largest social base and lets you compete with friends and family members, which helps keep you motivated and more likely to complete your daily step goal.

Sarah Tew/CNET

Should you buy it?

The Flex 2 is designed for two types of people: those who want a basic, affordable and waterproof Fitbit, and those who want a versatile and stylish fitness tracker. It excels at both. If you don't care about heart rate and can live without a display, the Flex 2 is the tracker to buy. Its slim and swim-proof design is what won me over.

If you want something a little more advanced, check out the Fitbit Charge 2.


Fitbit Flex 2

Score Breakdown

Design 8Battery 7Performance 8Software 9Features 7