Fitbit Flex review

Fitbit Flex review

T3 3
  • The Fitbit Flex is a wrist-worn fitness tracker that has the Nike Fuelband and the Jawbone Up firmly in its sights, but can it compete?

    Fitbit Flex review


    • Comfortable
    • waterproof design
    • Bluetooth 4.0 syncing
    • NFC connectivity


    • Battery life
    • Llimited display
    • No altimeter

    When Fitbit first introduced its dinky little fitness tracker it said that it was aimed at people who didn’t want their friends to know that they were step counting on the way to work or running up the escalator to earn badges so they let you put the tracker in a pocket or clip it onto your waistband.

    Now having introduced the Fitbit Flex, no doubt due to the popularity of charity wristbands and devices like the Nike Fuelband and the Jawbone Up, the company is now turning its attention to those who love to flaunt their fitness prowess.

    Cheaper than its rivals and stripping away some of the physical features from previous Fitbit devices, we put the Flex to the test to find out if it stayed on, or got chucked into the draw with the other failed fitness trackers.

    Fitbit Flex: Build and design

    The first main difference from the Fitbit One and the Zip is that now you can strap this device around your wrist like the Fuelband and the Up.

    Available in small and large sizes, the flexible rubber strap comes in a series of bright colours or in our case a more muted charcoal grey shade which is secured by clipping two little grooves into a series of holes depending on the most comfortable and secure fit.

    That rubbery shell hides away a detachable tracker that uses a row of white LED lights each one representing 20% of your goal and can be viewed through a thin strip of black plastic on the strap. You can simply wake up the display by giving it a couple of taps or three more to access the sleep tracking function.

    Unlike other Fitbit devices and the Fuelband, the Flex is waterproof which means you can take it for a swim. We took it for a dip and we can confirm that it was still in working order and despite having to glance to see if it was still there, did stay put.

    We like the idea of being able to view the time on the Fuelband which is notably missing from the Flex, but essentially comfort is the key concern here and we can safely say that the Flex is so light that is barely noticeable during the day which also makes it perfectly suitable to wear when you're asleep.   

    Fitbit Flex: Features

    The tiny tracker that records the data hosts the same accelerometer technology found in other Fitbit devices which enables you to track steps, distance, calories burned and sleep however there is no altimeter this time round which means you can’t record data on stairs climbed which is disappointing if you've swapped the lift for the stairs at work.

    A new Active Minutes feature which enables you to set goals based on the recommendation that you should do 20-30 minutes of exercise a day. When you meet your quote a simple vibration will let you know that you have clocked up your Active Minutes.

    One of the big advantages over its competitors is the ability to automatically sync over Bluetooth 4.0 and NFC which means you can see data in real-time. This is dependent on whether you have a compatible devices which covers the latest iOS products and a select few Android models, most of which are made by Samsung.

    You can still sync data wirelessly to Mac or a PC using the small USB dongle supplied.

    Of course it’s one thing to collect the data but analysing and recording is as an equally valuable part of the process and this is an area where Fitbit continues to impress.

    With iOS, Android and Windows Phone 8 apps the Fitbit dashboard has now been given a refresh making it a cleaner, more tablet-friendly place and now offers the ability to customize and move data around depending on what really matters most to you.

    The continuing support for apps like Endomondo, Nike+ and MyFitness Pal means you can still use other services that feed the data into the Fitbit dashboard tool or make the transition to the service entirely a much easier one.

    Other aspects of your daily routine like food and water intake still need to be manually updated which can be an arduous process if you can’t find the correct items but impressive if you don’t run or go to the gym: there's a huge database of activities which range from sweeping the floors to chasing cattle in a farm.

    This service remains free but if you want to get more tailored reports, you can opt in for the Premium package (£39.99) which will help you make more sense of your exercise, eating and sleeping habits

    Fitbit Flex: Performance


    We wanted to test out the accuracy of the Flex which we were told was around 94% compared to the Fitbit One which is closer to the 100% mark and also doesn’t have to account for some of the spurious movements that devices on the wrist can sometimes incorrectly register activity.

    We checked it for a simple test of how it tracked steps compared to the Fuelband and the One from a day’s journey to work and found that it offered only a marginal difference with the One and only a slight difference when compared to the Fuelband.

    Testing the real-time syncing with an iPhone 4S, the Flex worked as promised recognising when we were on the move and even a quick shake of the arm was enough to start seeing the data go up. We also tried seeing how the NFC fared trying out a Samsung Galaxy S3 and the connectivity lived up to its billing.

    We also loved that sleep tracking has removed that velcro strap from the equation, however setting it up can be tricky to master. Having to tap the device five times precisely then remember to do the same when you wake up in the morning is not always that straightforward.

    The battery life on the Flex is five days and it’s fair to say that it stays true to that which is somewhat disappointing when compared to the One which despite supposedly lasting for the same amount of time, went on for much longer. Like-wise the Fuelband can go for a few weeks before having to be charged.

    Thankfully though, it takes just under an hour to get back to a full charge when the battery is fully drained which has to be done by connecting it with the USB charger in the box.

    Fitbit Flex: Verdict

    In our time with the Fitbit Flex, it was difficult at times to get used to the fact that we couldn’t just quickly glance at our wrist to see how many steps we had achieved that day. We love the idea of real-time data but we can’t say that we were fans of having to take out another device to see it.

    We have no complaints about the build of the device itself which is robust, waterproof and also has a kind of understated style about it that meant we were quite happy to wear it all of the time. The software and tools behind the hardware are still some of the best for a fitness tracking device.

    If you are happy to whip out the smartphone to check your progress, the Flex is a great choice for the price in terms of what it can offer, but a little extra can get you a One that has a display, a better battery life and increased accuracy while a little more will get you a Fuelband that works as a pretty nifty watch as well.

    Fitbit Flex release date:  27 May 2013

    Fitbit Flex Price: £79.99

  • Fitbit Flex

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