Fitbit Flex 2 review

Flex 2 is a waterproof budget fitness tracker, and that's about it
Fitbit Flex 2

Fitbit Flex 2 is the first swim-friendly fitness tracker from the company and we can almost hear the collective sigh of relief.

In the face of the Misfit Speedo Shine 2 and gamut of other water-resistant trackers, it's taken Fitbit a long time to answer the call of swimmers. And on paper at least, the Flex 2 looks like the real deal.

Wareable verdict: Fitbit Charge 2 review

Priced reasonably at $99.95, the features aren't as advanced as the Fitbit Charge 2, which was released at the same time. Rather it's geared towards the entry level crowd who want a tracker that's slim, versatile and of course, waterproof.

Aside from the simplicity of form factor and usage, the Flex 2 is a far cry from the likes of its years old predecessor, and that's a very good thing. So how does it stand up during testing? Read on to find out.

Fitbit Flex 2: Design and comfort

Fitbit Flex 2 review

Flex 2 is a diminuitive little tracker that's hardly noticeable at all on the wrist, which is a nice change of pace. The wearable is much slimmer in appearance than the first Flex because the tracking module is 30% smaller. The Alta looks like a beast next to it. Okay, not really, but Flex 2 is noticeably more petite and is without a display. It's also the ideal piece of fitness tracking camouflage, especially when the module is tucked away behind a bangle or pendant.

In a Classic band, the textured elastomer is soft but not so pliable that you'll be able to clasp it easily. Yep, the dreaded button clasp is back and at this point I highly doubt it will disappear. Users have had issues with it since the early days of the first Flex, all the way until the Fitbit Alta. Speaking with reps, there are design methods behind the madness – it's made so the wearable won't fall off. However, that doesn't make putting on the Flex 2 any easier.

I've personally discovered various angles to finagle the Alta closed which I've used successfully with the Flex 2, but I can already see the frustration mounting in the comments section.

Fitbit Flex 2 review

Read next: Essential Fitbit accessories to personalise your tracker

If you want to change up your Flex 2, there are plenty of options. Unlike the old device, the new Flex is chasing the fashion conscious by letting wearers switch out the original bands for bangles, pendants and a whopping selection of seven Classic bands.

The colours you can choose from in the Classic collection are: black, navy, magenta, lavender, pink, grey and yellow. There are also $29.95 three-packs you can get with an assortment of colours, called the Sport Pack (navy, grey, yellow) or Pink Pack (magenta, lavender, pink). Alone, a Classic band isn't too expensive at $14.95.

The fancier options include Luxe bangles in silver ($89.95), gold and rose gold ($99.95). Then there are the pretty little pendants that come in silver ($79.95) and gold ($99.95), with a one size 17-inch chain.

Fitbit Flex 2: Notifications

Fitbit Flex 2 review

The device is similar to other screen-free fitness trackers where there are LED lights to notify you about calls, texts and also hourly reminders to move. Lifting your arm up will make the vibrations stop but the lights will keep flashing for phone calls.

At the moment, it doesn't seem like the lights can be personalised to your liking. Rather, Fitbit has a default pattern of lights and vibrations to help you differentiate between calls, texts, silent alarms, reminders to move and daily goal progress. No third-party notifications are recognised which I was annoyed with at first since half my texts are through Facebook Messenger. Then I realized I probably wouldn't be able to differentiate between the various buzzes and lights to tell if it's a text or Messenger anyway, making it a moot point.

In fact, it took awhile to get used to the meaning of the lights. But after several weeks using the Flex 2, I'm still just looking around for my phone when my wrist buzzes. The flashing lights simply don't do it for me. I've learned to recognise the magenta light celebration of reaching goals but everything else falls by the wayside.

Fitbit's explained to me that the team wanted to keep it simple for now but isn't closed off to the idea of customization. Right now, tapping on the Flex 2 shows your goal with a green light on top and white lights showing progression, the yellow light means alerts and blue stands in for both phone calls and texts. The latter is differentiated by a longer vibration for calls.

I'm hoping Fitbit will eventually allow customisation to make it more personalized. Thankfully the vibrations themselves aren't too jolting.

Fitbit Flex 2: Tracking

Fitbit Flex 2 review

The Flex 2 is as simple as you can get. It's capable of tracking steps, calories burned, active minutes, hourly activity and sleep, all of which can be auto-detected with the SmartTrack feature. Currently, the exercises that can be auto-tracked include walking, running, outdoor bike rides on pavement, elliptical, aerobic workouts (Zumba or cardio kickboxing) and sports like tennis, basketball and soccer (among others according to the app). I used the Fitbit Charge 2 and Samsung Gear Fit2 to measure the step counting and all matched up with the Flex 2 without any major issues.

You'll have to head to the app to see how many steps you've taken and to check on specific numbers for goals, but tapping on the front of the Flex 2 will elicit corresponding lights. Each white light represents 25% of your goal, meaning if your goal is 10,000 steps and you see four white lights, you've completed at least 7,500 steps. When you reach your goal, the Flex 2 vibrates and the lights flash in 'celebration'. Tapping again to check your progress will continue to show the same row of flashing lights.

Sleep tracking has been pretty good and I've used it against the Charge 2 – which has been pretty accurate – and the FitSleep device. On the whole, Flex 2 has matched up well with the Charge 2 and only a few wake-up times have been off. It also synced up with how much time I spent sleeping.

Unlike the Charge 2, there's no heart rate monitor or ConnectedGPS, which means you won't get running distances even if you take your phone along for the ride.

Fitbit Flex 2: Swimming

Fitbit Flex 2 review

Fitbit makes up for its lack of features slightly by allowing the aforementioned, glorious waterproofing and it can be worn up to 50m (including in saltwater). Swimming can be auto-tracked with duration and laps of four strokes monitored: freestyle, breaststroke, backstroke and butterfly. For non-swimmers, you won't have to worry about hopping in the shower with it on or heading out to the beach.

If you plan on swimming with the Flex 2, know that it won't give you the most advanced metrics. What you do get is an overview of your calories burned in a chart, the amount of time you've swam, distance, pace and impact on your day.

Specific strokes aren't noted in your app, and Moov Now remains one of the few swim trackers capable of this. You'll also have to turn on the swim track feature before you hop in the pool. Fitbit told me it's turned off by default to conserve battery life "for those who do not regularly swim."

Essential reading: The big swimming tracker group test

You must also swim continuously for SmartTrack to work. Meaning if you're not a strong swimmer, the Flex 2 has a harder time recognising your strokes. I was told the needed amount of active swimming is 15 minutes, but I've found you can change it to 10 minutes in the app. Pool length can be customised in the exercise settings of the app but I wasn't able to figure out where and how to do it.

In general, the tracking results were confusing. I swam a backstroke for 18 minutes then did 15 minutes freestyle – but the length and distance weren't captured for the backstroke. I did an additional 12 minutes of backstroke again and it still didn't record the laps. I'm not sure the length of the freestyle is correct either since the pool I swam in wasn't very long.

Fitbit has reached out to clarify a few points about swim tracking that I didn't realise before, and should actually improve swim tracking. In the account page of the Fitbit app, there are advanced settings for pool length and unit measurement you can change. It doesn't seem like much at first, but Fitbit says the algorithms can be tweaked according to pool length to more accurately calculate how many lengths you've swam and so forth.

Pausing in the middle of a swim can also throw off the tracking and the Flex 2 may not record it correctly after you check the app. So keep in mind: quick dips with a few laps likely won't get the same treatment as long, continuous swims.

One thing to remember is the inclusion of swim tracking is huge in itself. It doesn't have the other features stocked in higher-end fitness trackers like the Garmin Vivoactive or TomTom Spark, but the Flex 2 is definitely the cheapest of the bunch and you're getting what you pay for.

Fitbit Flex 2: App

Fitbit Flex 2 review

If you've used a Fitbit before, you'll know what the Flex 2 app looks like since it's the exact same interface.

It's a good ecosystem, full of social challenges with badges to earn, all clearly laid out and easy to use. The release of Flex 2 and Charge 2 came with a set of new challenges as well that are now available across the Fitbit lineup. Called Adventures, you can choose from various step goals that take you through different locations. For example, it takes 15,000 steps to 'walk' on the Yosemite Vernal Falls hike. That means every step you're taking at home, work, wherever is then matched up to the hike Fitbit's set up in the app. You even get to see your steps mapped out with the app telling you how many more steps you need to go. You don't have to complete the whole thing immediately, though the app gives you a daily destination with points to meet based on your seven day step average. Along the way, smaller step goals unlock little things to keep you motivated.

Aside from that, you get your usual gamut of food, water and weight logging. Days are presented on the main screen, and you tap a metric to get a broader look at your performance. For example, tap on the sleep score for the day and you can take a look at your sleep over time, and filter by day, week or month.

Overall, Fitbit's app is one of its strong points. Easy to use and clear, it offers enough data without feeling overwhelming. You can also sync up multiple devices to one phone. In the past it didn't always work right, and you'd have to un-sync, re-sync and go through a whole process but now it works like a dream.

Fitbit Flex 2
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Fitbit Flex 2: Battery

The five-day battery life of the Flex 2 is surprisingly mediocre. Of course, it's a matter of how you use the tracker, but I'd expect at least seven or more days since it doesn't rely on a screen for notifications.

For the first test run, I used it with call, text and notifications to move turned on, meaning it buzzed whenever these things happened. It was on to track activity as well. Interestingly, the Flex 2 stayed true to the paper description (unlike the Alta) and lasted five days.

Just for the heck of it, I turned off the notifications and only used it for activity tracking which resulted in about nine days of usage and counting.

Charging it is a similar process to the Fitbit Blaze: you have to remove the tracker module and insert it into the USB charger. We prefer the clasp style of Alta and Charge 2 for convenience, but it's not a deal breaker by any means. For such a small device that doesn't do that much, charge time took about two hours.

Fitbit Flex 2
By Fitbit
Waterproofing is easily the most exciting bit of the Flex 2, and that’s about it. The wearable doesn’t have any other standout features, making it the ideal fitness tracker for people searching for something basic and discreet, but it will leave others wanting. The Flex 2 isn’t terribly expensive but it also could be cheaper for what it offers. Regardless, if you don’t care there’s a screen missing – with haptics and lights your sole source for notifications – and don’t want to throw down money for a Fitbit Alta, the Flex 2 is your best Fitbit option for budget fitness tracking.

  • Waterproof in fresh and saltwater
  • Unobtrusive design
  • Very comfortable
  • Great price
  • Lacks major features
  • Difficult clasp
  • Charging time is long
  • Swim tracking results confusing

Shop for Fitbit trackers on Amazon

Fitbit Blaze
Fitbit Blaze
Fitbit Charge HR
Fitbit Charge HR
Fitbit Alta
Fitbit Alta
Fitbit Surge
Fitbit Surge

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  • JDonk says:

    Avoid fitbit! I bought a fitbit charge for my wife at dick smith. The first one did not work straight out of the box, would not charge at all. Dick smith replaced immediately, same day as purchase. A few months later the new one stopped charging. Again, Dick Smith replaced with a brand new item. Now, 9 months later, this 3rd fitbit charge will not charge, the battery will not charge.

    Subsequently, Dick Smith has closed down in my area so I can not return for a refund.

    I contacted Fitbit, who are saying the original purchase is out of warranty but they will replace with the same model, but will not refund. They don't have enough faith in their own product to give a warranty on the brand new replacement fitbit charge thats only 9 months old!! I asked if the replacement they are willing to send will have a warranty but they didi not reply.

    They also will not allow me to pay the difference to upgrade to a better model!!

    Well, if you ask me thats pretty poor, they should write a book on how to lose customers because thats what they've done in this situation. Not only me but everyone I know I tell how bad the product is and the lack of faith they have in their product. I strongly recommend buying a more reputable brand.

    Fitbit is a waste of money and you will more than likely be disappointed.

  • scarletanne says:

    Do the bands from the fitbit flex also fit the new fitbit flex 2?? 

    • l.prasuethsut says:

      No, the new Flex is a completely different design.

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