FitbitFlexPedometerI chose the Fitbit Flex Wireless Activity and Sleep Wristband Pedometer for my next review for many reasons. It is a bestseller with excellent customer ratings for its accuracy and reliability. All very good points but I was curious to find out more about its computer and mobile device connectivity and all that it entails.

From researching all its features it certainly sounds amazing.The Fitbit Flex syncs automatically and wirelessly to your computer and mobile devices. With free online tools and a mobile app, it can log steps taken, distance traveled, active minutes as well as sleep, calories burned, food and water intake, body mass, weight, your goal progress and the list goes on. It even has a silent alarm. You can even connect with other friends using Fitbit or join the Fitbit Facebook group online where you can share information and even set up competition challenges.

Table of Contents
Click ahead!
1. Computer & Mobile Device Connectivity 2. No Control Buttons? 3. Tracking Modes
4. Tracking Accuracy 5. Logging Data 6. Dimensions & Weight
7. Ways to Wear 8. Battery Info 9. Accessories
10. Pros 11. Cons 12. Consumer Reviews 13. Price

Amazing, right? But how tech savvy does one need to be to set it up? Would all this online data management prove to be more complicated and time consuming than its worth?

I have to admit too that the thing that got my attention is the display or rather the lack of one. The wristband just has 5 LED lights. Where are the buttons? It just proved too intriguing not to find out more about it.

Easy Computer & Mobile Device Connectivity

For anyone who is a little unsure about dealing with all this tech stuff, no need to worry as the website is a pure gem. It has extensive general information about the Fitbit Flex as well as incredibly easy to follow, well-detailed instructions regarding setting up and syncing your computer and mobile device to your Fitbit Flex. Check it out here.

FitbitFlex ConnectivityCOMPUTER SETUP:
The Fitbit Flex is compatible with both PCs (Windows XP, Vista, 7, 8) and Macs (OS 10.5 or later) with a USB port and, of course, internet connection.

PC browsers that are supported are: Chrome 12 and up, Firefox 3.6.18 and up and Internet Explorer 8 and up. MAC browsers that are supported are: Chrome 12 and up, Firefox 3.6.18 and up and Safari 5.0.5 and up.

All you need to do is download and install the Fitbit Connect software from the Fitbit website and follow the really simple and easy step-by-step instructions to create your account, charge and sync your Fitbit Flex to your computer and mobile device. The instructions are also available in their manual that you can download here.

MOBILE DEVICE SETUP (smartphone, tablet):
The Fitbit Flex uses Bluetooth 4.0 for iOS and Android mobile devices.
Android devices include: Samsung Galaxy Note 10.1, Samsung Galaxy Note II, Samsung Galaxy S III, Samsung Galaxy S4.
iOS devices include: iPhone 4S, iPhone 5, 5S, 5C, iPod Touch (5th gen.), iPad 3, iPad 4, iPad mini.

All the mobile devices that are compatible are listed on the Fitbit website. If your device is not compatible, all you need to do is download the Fitbit App from the Apple iTunes or Google Play links found on

Unfortunately while many Android phones have Bluetooth 4.0, some may still not be able to access the Fitbit App. I like that Fitbit asks you to keep checking back on their site for updates if your mobile device is not supported as they continually keep working to add devices to their supported list.

The Fitbit Flex Pedometer also works with other apps such as Lose It! MyFitnessPal, SparkPeople, Microsoft HealthVault, Digifit, MapMyFitness, Runkeeper, and Endomondo and more, which can provide extra valuable information. For example, although the Fitbit Flex does not monitor heart rate, users with cardiovascular problems report using the Fitbit App with Tactio which is able to track health indicators like blood pressure, LDL, HDL, and blood sugar. Again the full list of compatible apps are list on the Fitbit website.

Where Are the Control Buttons?

FitbitFlex-LEDAnswer: There are none! The Fitbit Flex Wristband Pedometer doesn’t have a display, it just has 5 LED light indicators on the band. That’s it! The only control button you need is your finger tapping on it. Simple but enough to provide you with a whole slew of feedback information which includes:

GOAL TRACKING – Each fully lit indicator represents 20% progress of your total goal value entered on your dashboard or Fitbit App. Only one goal at a time can be entered be it for steps taken, calories burned or distance traveled. To check your goal progress during the day tap the Fitbit Flex twice. What stage you are in currently is shown by a blinking light and any stage completed is shown by a solid light.

So if you set a total goal of 10,000 steps for the day and complete 2,000 steps, you will have one solid light and one blinking light. How will you know when you’ve reached your goal? The Fitbit Flex will vibrate and all the LED lights will flash. What fun… a pedometer that celebrates with you!

SLEEP MODE – Not only does the Fitbit Flex track the time you sleep but also your activity during sleep, that is, how many times you woke up and any restless movement. It lists how long each of these thing happen, how many times a night they happen and at what time they happen. Your sleep pattern data can be very helpful in determining and improving sleep quality, which is very important for your overall good health. As clearly stated by the CDC (Centers for Disease Control and Prevention), “Insufficient sleep is associated with a number of chronic diseases and conditions, such as diabetes, cardiovascular diseases, obesity, and depression. Sufficient sleep is increasingly being recognized as an essential aspect of chronic disease prevention and health promotion.”

By correlating your sleep pattern data to other data logged such as the food you ate, how much and how long you exercised and any medications you took, what time you went to bed, you can identify your sleep problems and figure out your triggers for sleeping better. Users have even reported taking their logged data to their doctors who were able to diagnose problems like sleep apnea or parasomnia, two conditions that occur while asleep with no memory of it when awake.

And what about all this wonderful news lately that adequate sleep helps with weight loss. Now that would be my first incentive to working my way to a better sleep!

Tap your Fitbit Flex quickly for about 2 seconds to activate the sleep mode. It will vibrate and show 2 dimming lights which will change to 2 blinking lights moving side to side. To exit the sleep mode when you wake up in the morning, once again tap your Fitbit Flex quickly for about 2 seconds until the Flex vibrates and all 5 lights flash.

Good to know that if you forget to set the sleep mode on you wristband, you can conveniently just log your sleep time from your computer or by using the Fitbit App.

SILENT ALARM MODE – Silent alarms can be set up by using your computer or mobile device. Besides setting up the alarm to wake you, you can set alerts as reminders of appointments, to take your pills or vitamins, to call your mother, or of a friend’s birthday. You can set up to 8 alarms to recur on a daily basis or just for a singular time but be aware that the more alarms you set, the less the battery life.

When the alarm goes off you will feel a gentle vibration (so it won’t wake your partner too) and all the lights will illuminate. This will repeat 3 times in 9-minute intervals or until you shut off the alarm which you can do by waiting until the vibration stops and simply tapping a few times until a center light appears and then fades.

CHARGING – Each LED light shows progress while charging by pulsing every few seconds to indicate the battery level. You will know when your battery is fully charged when all 5 lights will blink.

To charge the Fitbit Flex, remove the tracker from the wristband and place it in the charging cable until you hear a click. Plug the charging cable into a USB port of your computer or a UL-certified USB wall charger. When fully charged, insert your tracker back into your wristband.

UPDATING – LED lights will alert you if a recently released update done using your computer or mobile device failed to install by moving back and forth repeatedly, from left to right. Your Flex may then no longer respond to taps, charging, or resets.

What Activities Does It Track?

FitbitFlex-trackOnce you create an account, log in, charge and sync up your Fitbit Flex Pedometer to your computer or mobile device and to the dashboard, you have the option to track the following:


After initially entering some basic information like age, weight and height, calories burned are calculated by taking the base calories you burn without doing anything and adding in the calories consumed and activities and time spent doing the activities that you logged throughout the day.

As mentioned before, sleep time tracking includes the time you were asleep and number of times you woke up or were restless and for how long, and gives you an overall sleep efficiency rating. Users with sleep problems such as sleep apnea have report benefiting from this information concerning the quality of their sleep.

How Accurate is the Fitbit Flex Pedometer?

The Fitbit Flex Pedometer uses a MEMS 3-axis accelerometer that measures your movements and calculates your calories burned, distance traveled, steps taken, and sleep quality. Fitbit claims that the Fitbit Flex is one of the most accurate wristband pedometers. Scouring numerous customer reviews I found that users overall agreed and were pleased with its reliability and accuracy.

However, its accuracy can be compromised if you engage in activities where you use your body a lot more than your arms or even where you move your hands a lot. In those cases you are probably better advised to use a clip pedometer for more accurate tracking.

Fitbit-Flex-girlAs for its accuracy regarding other activities:
Treadmill: You will have a more accurate reading if you swing your arms as you walk or run on the treadmill. If you don’t, users have suggested putting the wristband on your ankle or in your sock.

Swimming: Although the Flex is water-resistant and can be submerged up to 10 meters, it does not track swimming. You can, however, log it as an activity on your dashboard and the time performing the activity is used to track it. You can also view the amount of calories burned. I would recommend not using for extended periods of time in a chlorinated pool as the chlorine can be pretty damaging to the wristband. It would be advisable that once out of the pool to rinse and wipe it clean of any chlorine residue.

Elliptical Machine, Stationary Bicycle, Cycling, Running, Stair Climbing: These are all activities that the Flex does not track but that you can log as activities on your dashboard to see stats for the number of calories burned and active minutes. However, like the treadmill, some users have reported accurate tracking with these workout activities by placing the Fitbit Flex on their ankle or in their sock.

Interesting to note that it is possible to get tracking for some of the above activities by syncing your Fitbit Flex with compatible apps. One example is if you want to track your running, you can use the iRunner app.

Since the Flex is a wristband pedometer, questions arise whether it tracks activities like driving, using your mouse, typing and writing. It may but not enough to make a difference and this might be the reason Fitbit suggest wearing it on the wrist of your non dominant hand. To reduce over counting of steps, change your settings to “Dominant” to decrease sensitivity and if the Fitbit Flex is not counting enough steps, change your settings to “Non Dominant” to increase sensitivity.

What Data Can You Log?

FitbitFlex sleepThe Fitbit Flex tracks the most recent 7 days of detailed, minute-by-minute data. It also tracks your daily total for the past 30 days and summarizes your daily calories, distance traveled, steps taken and sleep quality.

Your free membership to allows you to track and log details about activities (especially useful for those that your Fitbit Flex doesn’t track), sleep (useful when you forget to set your sleep mode), weight, food and water intake and much more. If you wish to log even more detailed information, you can subscribe to a premium service that is available at a cost.

Most impressive to me is that you can sign up online for a free account and try out dashboard without having to buy any of their pedometers first. Check it out here. This is a great way to have a look at the dashboard and how it works to see if you will be comfortable using it.

You can customize what you want to see displayed online. For example, with help for weight loss and maintenance, you can manually create a food plan and keep a food journal and activity log which allows you to clearly see calories in and calories out each day. It will even register logs from a Bluetooth scale!

Goals can be set for steps taken, calories burned, distance traveled, or active minutes. You can only set up one goal at a time but you can change the goal and/or its value on the dashboard whenever you wish. Once set you can follow your progress to your chosen goal on your dashboard.

You will even receive an email once a week of your weekly stats (that you can print out if you wish) and an alert if you are nearing a goal. Whenever you reach a goal whether a daily, weekly or lifetime one, you will be awarded badges.

You can also keep a check on the battery level and any upcoming alarms or alerts.

Best of all, I love that the latest data can be synced wirelessly to your computer or mobile device.

Dimensions & Weight

The 2 wristbands included in your purchase come in 2 different sizes. The large one measures 6.3 – 8.2 inches (or 161-209 mm) and the small one measures 5.5 – 6.9 inches (or 140 – 176 mm). Both sizes measure 0.6 inches (or 13.99 mm) in width.

The small wristband weighs 13.4 grams and the large one weighs 14.6 grams.

Both wristbands are adjustable with several notches should you need to tighten them more. If you want to see how the bands will fit your wrist, you can check out the handy Fitbit Flex Wristband Sizing Tool here where you can download a cutout with the actual dimensions and measure it on your wrist.

How & Where to Wear It

FitbitFlex coupleThe Fitbit Flex Wristband Pedometer obviously should be worn on your wrist although Fitbit states you can remove the tracker and wear it in your pocket. Wearing it on your ankle is not recommended. You can wear it on either wrist but wearing it on your non dominant hand usually gives the most accurate results.

The wristband is made of durable, flexible elastomer material. It is slim, light and comfortable to wear 24/7. There have been a few cases of allergic reactions to the band. A clasp made from stainless steel fastens the wristband.

The Fitbit Flex is water-resistant (not waterproof) so you don’t have to worry about sweat or rain and can even wear it in the shower. However, I strongly advise not to wear it while swimming but rather to log the activity instead.

There are many user complaints that the wristband is difficult to get on and off but as one customer suggested if the face of the Fitbit Flex is pointed down the band becomes quite easy to put on and remove. Instructions and diagrams for inserting the tracker into the wristband and securing the wristband onto your wrist are clearly shown on the Fitbit website.

Cleaning the Fitbit Flex is fairly easy. You must remove the tracker from your wristband and then rinse the wristband. You can use warm water and a mild detergent or a cotton swab and rubbing alcohol. Avoid using abrasive cleaners. With a cloth or paper towel dry the tracker and the wristband before replacing the tracker back in the wristband.

Battery Info

The Fitbit Flex uses a rechargeable lithium-polymer battery with a battery life of about 5 days. Customers have reported it taking anywhere from 1 to 3 hours to charge. Make note that the more alarms you set and the more frequently you tap your Fitbit Flex, the more the battery life will decrease.

Recharging the battery is an easy process. You just remove the tracker from the wristband and insert it into the charging cable supplied which you plug into the USB port of your computer.

If you have problems charging, the charger and the sensor contacts may need to be cleaned. Use a cotton swab lightly dipped in rubbing alcohol. You may also try plugging the USB dongle into an outlet with a converter so as not to worry about the computer going into sleep mode and stopping the charge.

Accessories Included & Not


  • Wireless sync USB dongle
  • Flex Tracker
  • 2 Wristbands – 1 small and 1 large
  • Charging cable

Black or slate wristbands are the standard colors available on Amazon, although Fitbit includes on their website the pink and lime wristband colors.


  • Navy, tangerine or teal
  • Navy, tangerine and teal Flex wristbands in packs of 3 (packs come with one clasp)
  • Individual wristbands in black, slate, teal, tangerine, pink, or navy (available in small or large)


  • Access your stats anytime on your computer or smartphone
  • Syncs data wirelessly
  • Compatible with both PCs and Macs
  • Compatible with both iOS and Android mobile devices
  • Free online tools and apps to track data
  • Excellent website with extensive information and instructions
  • Water-resistant, no need to worry about sweat or rain and you can even take a shower wearing it
  • Overall accuracy and reliability highly rated by users
  • Silent alarm feature to wake you up or set an alert
  • Very stylish with the great colors available
  • Lightweight and comfortable
  • Can be worn 24/7
  • Users report excellent customer service and support
  • Fitbit has a great online community with its Facebook group and help forums
  • 45-day Satisfaction Guaranteed Return Policy and 1-year Limited Warranty based on the date of activation
  • Beneficial for people with health problems with daily monitoring
  • Celebrates with you when you reach your goal by buzzing and flashing lights


  • Biggest complaint by many users is the poor clasp design that has a tendency to pop open resulting in possible loss of the tracker.
  • Customers report that the wristband is sometimes difficult to put on and securely fasten
  • Has no display face, just 5 indicator lights
  • You need to manually enter activities that are not walking such as lifting weights, stair climbing and swimming to properly estimate the calories you burn
  • Apart from tapping on the wristband to follow your daily goal progress, you need to access your computer or mobile device to see all the other data activity which could be tedious if you don’t have a smartphone or if the website is down
  • When website is down, you cannot sync your latest data
  • Does not display time, although when you connect to your computer or mobile device the data collected includes the time and date of all the events (steps, sleep pattern, etc.)
  • Some users reported allergic reactions to the wristband
  • Does not differentiate between deep sleep and light sleep
  • Nothing on the band that indicates when the battery is low so you need to check your online data
  • If you are a heavy sleeper, the alarm’s vibration may not be enough to wake you
  • No GPS tracking
  • No altimeter to track stair climbing

Consumer Reviews of the Fitbit Flex Activity + Sleep Wristband

The Fitbit Flex pedometer is an Amazon bestseller that comes highly rated by its customers with over 1000 users giving it 5 stars and over 500 users giving it 4 stars.

Customers also give high ratings to Fitbit’s customer service. I know it can be frustrating but it might be worth taking the time to contact them and give them (or Amazon) a chance to help you out especially with their great reputation for support. I was pleased to see Fitbit Support responding to customers complaints on Amazon and offering to help resolve their problems by advising them to open a case file at with a link to their Amazon review.

In addition to Fitbit’s included warranty, customers recommend getting Amazon’s additional SquareTrade 2-Year Personal Care Protection Plan.

The Price is Worth it for the Fitbit Flex Wireless Wristband Pedometer

The cost is in a higher price bracket of just slightly under $100. If this is over your budget, I would suggest to keep checking Amazon at intervals for its always ongoing discounts and deals.

While in general the Fitbit Flex might have a higher appeal to the younger crowd that are more tech and app experienced, older and less tech savvy users have reported that it is very easy to use and set up. You can use the online tools and apps as simply or intricately as you wish and that makes it popular with all age groups.

Filed under: Reviews

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