Fitbit Flex 2 Review

We purchased the Fitbit Flex 2 so our reviewer could thoroughly test and assess it. Keep reading for our full product review.

These days, wearing an activity tracker on your wrist seems like a given. (I mean, are you even an active person if other people can’t tell you’re tracking your stats? Kidding of course!) But when the original Fitbit Flex debuted way back in 2013, it was actually the first wristband wearable to market. Since then, this particular device has set the standard for all wrist-based trackers, and while the original sensor’s tech has improved (pretty significantly, at that), the basic design—simple, sleek, and unobtrusive enough to be worn next to a watch—has stayed pretty much the same. 

The Fitbit Flex 2 improves on the original in a few really important ways, though: The tracker module is removable, making for easier cleaning, and it’s not just water-resistant for showers and dishwashing—it can actually handle being fully underwater. Of course, the device still tracks your steps taken, distance walked, and calories burned, and you can track even more health-related data within the user-friendly, recently redesigned Fitbit app. Read on to see if this tracker is the one that can help you reach your goals. 

Activity Tracking: Covers all the basics

Using its built-in accelerometer, the Flex 2 automatically tracks steps taken, distance walked, and calories burned; one thing missing is an altimeter, so you can’t see how many stairs you’ve climbed per day. A strip of LED lights on the band will light up when you’re nearing your daily step goal or when you’ve been sitting for too long. The device also automatically tracks your sleep quality, logging when you fall asleep and when you wake up (you can even set a goal for how many hours you want to sleep, and the device will wake you up with a gentle vibration versus a blaring alarm).  

In addition to tracking those basic metrics, the Flex 2 improves upon the original version with the addition of an exercise recognition feature called SmartTrack that automatically picks up select high-movement activities—like walking, running, outdoor cycling, sports, aerobic workouts, elliptical workouts, and even swimming (the device is waterproof up to 50 meters and will track your laps swam and calories burned in the water, something most budget trackers are incapable of)—and record them in the exercise section of the app. Just a heads-up: Because there’s no GPS, you won’t get much more data from your cardio workouts than calories burned and how that factors into your day’s activity. Even without heart rate tracking and GPS, I found the numbers to line up with those recorded by my Apple Watch, which I wore simultaneously.

That automatic tracking is great for beginners who are just starting to monitor their behaviors. (FYI: Swimming isn’t tracked automatically because its effect on the battery charge, so you’ll have to turn on that capability via the app and set the pool length if you want to track your laps.) As someone who does all kinds of workouts, I liked that I didn’t have to remember to press “start” at the beginning of a run, but it was frustrating to have to remember to manually add something like yoga or a low-intensity weight session to the app after the fact. 

Design: Sleek and comfortable

The Fitbit Flex has been slim and minimalistic since its beginning, and the Flex 2 is no exception—this version, though, is 30 percent smaller than the original at less than half an inch wide. The tracker module, a tiny plastic rectangle, pops into a skinny rubber strap; a two-pronged steel clasp, which, despite being significantly more difficult to secure than your average watch buckle, keeps the device right where it’s meant to be. It comes with two bands in different sizes for the perfect fit, and you can swap out the standard strap for more colors or fancier bracelets and pendants, although those will definitely jack up the price.

There’s no bulky screen on which you can view your metrics (there isn’t even a clock to check the time on the front); instead, color-coded LED lights notify you when it’s time to move (each light represents 20 percent of your daily goal) or when you receive a text. To understand or customize the color-coding system—purple means move, yellow signals an incoming call, and blue means you’ve got a text—you’d have to read the user manual, which felt like extra effort I didn’t really want to exert. Without that screen, though, the whole thing comes in at less than half an inch thick and under an ounce—you’ll barely notice it’s there when wearing it. 

The App: User-friendly and intuitive

Because of its minimalist design, this Fitbit is actually a little tougher to use than higher-tech options. Again, because the LED light display is so discreet, you actually have to read the user manual in order to decipher them—and who has time for that? 

Your main control center is the partner app. Pairing your device via Bluetooth with your iOS, Android, or Windows devices is super easy when you follow the setup prompts; it took me less than five minutes to have my Flex 2 up and running. 

The app is also where you can really dig into your metrics. Not only can you view your steps taken, distance covered, calories burned, active minutes, and sleep activity, you can also manually add your weight, exercise, food and water intake, and even menstrual cycle. Fitbit also provides personalized recommendations based on your fitness goals and the data it records, which is super helpful for people who are looking to develop specific habits. 

The Fitbit app recently got a makeover, and it’s easier than ever to view your info on the main screen, which prominently displays all the basics upon opening. Scroll down, and you’ll find all the categories where you can add the info manually. The app stores all your data separately within each category, so you can easily compare patterns over time. 

Battery life: Not the best

My one complaint with this device was the battery charge; while the company says it lasts up to five days, that’s counting on a full charge to begin with. I found I never really had time to let the device sit for the nearly two hours it needed to reach a full charge, so I ended up having to re-charge it over and over again. Other online reviews have also noted sub-par battery life, and this may be one area in which the company skimped on functionality in order to keep the device’s size so small. 

Price: Totally reasonable for what you get 

Retailing around $100, the Flex 2 is one of the most affordable fitness trackers out there with this set of functionalities. Yes, there are cheaper options like the Xiaomi Mi Band 3 or the Letscom Fitness Tracker HR, both of which I reviewed, and both of which ring up at around $30. However, by investing in the Flex 2, you’ll be covered on all the basics and have access to the Fitbit app’s in-depth data deconstruction, which makes this a perfect choice for people just dipping their toes into the wearable market. If you do want more advanced capabilities, though, you’re going to have to be prepared to shell out even more. 

Competition: This is an entry-point into the world of wearables

Fitbit has a number of wearables, from the Fitbit Alta HR, which retails for $149.95, to the Fitbit Versa Smartwatch, which retails for $199.95; these devices do offer more advanced features like heart rate tracking and GPS capabilities, which may be appealing to more intense athletes or even people who are more focused on specific weight loss or fitness goals. And, of course, there are more sport-specific watches like the Garmin Forerunner 35 and mainstream options like the Apple Watch that deliver even more fine-tuned insights. 

But the accessible price point, basic metrics, and intuitive app all make the Flex 2 a no-brainer for those who are new to activity tracking and want to start monitoring their habits without shelling out a couple hundred bucks.