Fitbit Flex review – Your new personal fitness instructor

fitbit-flex-review“Starting next Monday I’m going to eat healthier and exercise “– I think most of us have given that promise to ourselves, but the lack of time, desire and motivation typically become excuses to wait for the right Monday. However, if we had a personal trainer to help us out with our diet and monitor our workouts, we’d probably follow his recommendations. Now the waiting for that Monday to come has come to an end, because the California Company Fibit has made sure to provide each and every one of us with such a trainer. And here, today, you are going to read all about it – the Fitbix Flex tracker.

Fitbit is a Company based in San Francisco, California, also known as Silicon Valley. James Park and Eric Friedman are in charge of management. They started manufacturing this type of innovative fitness and health helpers called trackers back in 2007.

fitbit-flex-review-2The Fitbit Flex tracker is a part of the next-to-last generation, introduced in May 2013. It is the first of their products to be worn only on the wrist. That’s what makes it so convenient, unlike the other trackers which you would put in your pocket or attach to your belt, or some other piece of clothing, it can’t be lost or forgotten that easily. The device can track the number of steps you make, the distance you’ve passed and the calories you’ve burned. It can monitor how long and how well you sleep. The wristband keeps you informed about the amount of water and calories you consume. It sets daily goals, it gives you opportunities to compete with your friends and win badges, and it also evaluates your results using five LED lights.

Below we will be offering a full description of the potential and purpose of this personal “coach”. You can decide if Monday will come tomorrow.



In the package you will find the Flex tracker, two wristbands – a large one and a small one, both with a special jack to fit it on the inside. Once placed there, the chances of it falling off are minimal.




Also in the set is a USB charging cable. The box also contains a “dongle”, also known as a hardware key for wireless synchronization with PCs/MACs, and a guide which leads us to the official website of Fitbit, straight from its cover. You can find a very detailed user manual describing all the functionalities in about thirty two pages. After a necessary registration your profile will accommodate all the data from the usage of the product. To be completely accurate, we could say that Fitbit Flex tracker is the key to a vast space of options and commands which we can set on our own. We will let you know more about how to manage it all a bit further down in the review.


Design and construction

While talking about the design of Fitbit Flex we will focus on the rubber wristband, which is the accessory-keeper of the tracker. We should first mention that on The 20th of February 2014, the Company stated that they are working with the Consumer Product Safety Commission. The band weighs only 13 grams and it’s designed for sports. As we mentioned, you can choose between two sizes and a variety of colors.


The design is clean and the width of the band is 13.9 mm. For this elegant new look Flex changed the OLED display (which is still available in some of their other products like “One”) in favor of five LED lights, which we can see through the built-in transparent window. When you place the tracker in the jack of the band those lights fit right under it. The purpose of this construction is to send different commands to the tracker via tapping on the window. For example, if you want to see how you are doing with the daily assignments, you have to tap twice for the LED lights will appear. One light equals 20%. The fastener of the band is similar to what you would get in a wristwatch – convex rubber elements on one side go into slightly smaller cuts on the other. When you’re putting it on for the first time you might experience some difficulties, but afterwards you won’t have to worry about the stability of the grip. This way you’ll be ready for a dynamic day or a good workout.





Recharging the tracker takes about two hours. The battery is lithium-polymer and able to last up to 7 days. While recharging, the LED lights appear one by one. Again, one light equals 20%. You can track the energy level in your profile on, while reviewing your accomplishments and setting new goals.


Specs sheet


Display None (Management by indicator LED lights and touch sensitive panel)
Sensors3-axis MEMS accelerometer (tracks calories burned,distance passed , steps made, quality of sleep)
ExtraVibrating motor for silent alarm, Bluetooth 4.0, water resistant (max 10 m.)
MorePC and MAC requirements: Windows XP/Vista/7/8, USB port, Internet connection; Mac OS X 10.5 (or newer), USB port, Internet connection; Working temperature (-20 ° to 45°C); Maximum operating altitude – 9144m.
Batterylithium-polymer (5-7 days life)
Weight13 grams
Thickness11.10 mm


Fitbit Flex is a device you can carry around with you all the time, except while the batteries are being recharged. (We recommend you to do it every 3 – 5 days to be sure that the sensor is working properly).

Throughout the day the tracker counts the steps you make, the calories you take and the distance you pass. In the night it monitors your sleep and it wakes you up with a soft vibration. This is designed for the potential person next to you, allowing him or her to sleep a little more.

You don’t have to take the wristband off during your morning shower, because it’s water resistant. Even if you feel like swimming, you can go with the Flex tracker which can be submerged to a depth 10 m. (higher pressure caused by greater depth affects the accuracy of the calculations)


If prefer heights instead of watery depths, you should know that the maximum operating altitude is 9144 meters. This shouldn’t bother you since mount Everest goes up to a measly 8850 meters. (according to most recent data) The Himalayas keep growing with about 5 centimeters per year, but we’re certainly a long way away from 9144. If you’re taking on an extreme approach like this, you should consider that Flex can work in a temperature amplitude of -20 to +45 degrees Celsius.


Of course, the tracker’s abilities don’t end there. We’re about to introduce you to the more interesting part of its functions. Besides counting calories Flex can help you improve your physical condition. It motivates you to be more active and train more by setting daily goals. When you accomplish them the tracker congratulates you with a vibration and when you log in the website it awards you with a virtual badge.


Fitbit helps you fight the extra pounds. In order for the product to track this process it is necessary to fill in your current and desired weight. Also, to be more precise you have to type in the amount of calories you’ve been consuming. Counting calories may seems complicated and boring to you, but you might be proven wrong because Fitbit has attempted to create a very detailed database of foods and drinks. They’re organized in user-friendly tables. You just have to pick whatever you’ve eaten during the day to see the amount of calories you’ve taken. Considering both your intake and the energy you’ve burned, Flex will monitor how you’re doing with the goal and inform you when you achieve it.


Perhaps every one of you has noticed that when you train with somebody else you get better results. That’s because our instinct to compete kicks in. If it doesn’t, at least a collective workout would be more fun. Fitbit appreciates this fact and provides you with an option to find new friends who also use their product and contact them through email or facebook. Once you’re connected you’ll be able to organize online tournaments, rankings and new challenges.


Speaking of social networks, we can’t go without mentioning the option to share your achievements. This is a way to inspire more of your friends to work out and share their results. We can’t deny that sharing such information in facebook is contagious. We’ve all seen pictures taken in the gym with the sole purpose of being shared on the network. This way we get to brag about how many km we’ve passed and infect somebody with the fitness bug.

Don’t get the impression that Fllex can be managed only through a PC or MAC. We’re happy to inform you that the software is also available for your smartphone and tablet. You just have to download the Fitbit application. I think we can safely say that the app is more convenient than the web software.



When setting up the tracker you have to open After a necessary registration, Fitbit has prepared a picture guide, explaining how to put the tracker into the rubber band and complete the synchronization between it and the PC by using the dongle. In the profile you should specify your gender, height and weight in order for our instructor to start working.

Notifications can be sent when the battery is low, when you receive a badge, a friend request, or a new message, for a competition or daily/weekly/annual reports and so on. You can choose to receive them in email or on your smartphone.

From the “devices” menu you can set your daily target – number of steps, distance, calories to burn or active minutes. You can even put in on which arm you carry the device and whether you move a lot during sleep. That data is recommended if you want the tracker to do accurate analysis.


From settings you can set an alarm. We remind you that this alarm is actually a soft vibration. If you decide to share your results it’s a good idea to pay attention to the personal space tab. There you will find a table with all of the possible activities that can be shared publicly, with your friends or just with you.


In the right corner of your account, in addition to the settings menu, you’ll find an icon for your profile, where you can add or change information, also an icon for messages and badges.


In the “log” department you can keep notes about everything that’s going on with your health and body.


For example, if you think that there is no way to track the calories of the food you’ve eaten, perhaps you’re wrong. The database has information about things we didn’t even know existed. This menu can monitor another important detail – how much water you drink.


In the activities category you can add the sports that you’ve done.


From “Weight” you can set your desired goal and a deadline.


In the “Sleep” category you can see a full sleep diagram. It has information about the time you’ve been asleep and awake. An important thing you should know is that in order to set the tracker into sleep mode you tap the LED lights a few times. It will vibrate and display two lights that will slowly fade away. This means that sleep mode is active. In the morning, when the vibration wakes you up, you should repeat the same thing to get out of sleep mode.


In “Journal”, besides making notes you can fill in your current mood and allergies.


Apart from these options Fitbit Flex invites us to pay for some extra options. Among them you can find personal reports which help you find the changes you need to make to improve your health, also some deep analyses of your activities. You will get the opportunity to compare yourself to the other owners of the tracker, gaining access to similar databases with their activities, weight and sleep quality. A full list of the options from the Premium package can be found here:

We will end our “manual” with some words about the design of the board where you track your progress. The balance between statistics diagrams and small funny icons is good. You won’t get bored while exploring your results because of the pleasant colors.

We don’t think that you’ll find it difficult to use the software. We see a lot of similarities between its design and Facebook.


fitbit-prirodaThe Flex wristband is practical and convenient but the question is – Is it comfortable while sleeping? We are concerned with its width of 11.1mm. To be precise, the discomfort comes from the slightly thicker end near the transparent window. If you are used to sleeping with a watch or a bracelet you won’t be disturbed by the 13 grams of the Flex.

About calculation accuracy we’d say that it’s relatively good. Not necessarily a 100% correct, but considering that it doesn’t use GPS the results are pretty good.

Unfortunately, Fitbit Flex doesn’t monitor your heart rate or climbed stairs but for its price it offers a beautiful and simple design with practical functionality. If you are looking for a fitness tracker to review your progress and stimulate you further on a budget, you can count on Fitbit Flex.

In conclusion we could say that Fitbit Flex is a smart, functional and useful gadget we could all use to improve our eating habits and physical condition.


  • Simple elegant design
  • Good price
  • Light and comfortable body
  • Water resistant
  • Accurate
  • High battery life
  • Discrete alarm (vibration)


  • Lack of OLED display
  • Doesn’t monitor heartbeat
  • Takes time to get used to sleeping with it

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