Fitbit Charge 2 Heart Rate Fitness Tracker – User Review | GadFit

November 22, 2016

I’ve been holding on to the Fitbit Charge 2 ($149.95) for a while now and just couldn’t quite sit myself down to complete the review. With more comprehensive fitness trackers such as the Forerunner 35 and Polar M200, Polar M600 and even the Apple Watch Series 2 that caught my attention easily, I simply had to give myself some time to moderate my expectations before looking at the Fitbit Charge 2 again.

I had the fitness tracker for close to 2 months now, #truestory, and here’s what I have to say.fitbit charge 2-feature



  • All day activity tracker. Counts steps, distance, active time, calories, floors climbed, active duration and sleep
  • Wrist based heart rate monitoring
  • Connected GPS
  • Vibration enabled for alarms and smart notifications and guided breathing
  • Multiple exercise profiles
  • OLED display
  • Cardio Fitness Score
  • Breathing guide
  • Changeable wrist straps
  • Wireless syncing
  • Battery life listed as up to 5 days
  • Robust mobile app platform
  • Splash-proof; not suitable for swimming
  • DND mode (Updated 22nd Dec 2016)
  • Workouts can be paused and resumed


  • Lack of GPS at high pricing
  • Not suitable for swimming

As usual, I’d suggest you brew a cup of coffee or tea, sip slowly as you read through the review and enjoy the pictures. Drop me a note if there are any queries you may have which I didn’t manage to answer.


The Fitbit Charge 2 fitness tracker has a removable core which is flanked by changeable wrist straps that wears like a watch; the strap is mildly elastic.

This is a strong selling point because Fitbit has prepared various options for band customisation ranging from leather to special edition straps with beautiful beveled diamond texture; at a premium of course.fitbit charge 2-split-viewFor those of you who are unaware, the previous Fitbit Charge HR was moulded into the strap and the buyer pretty much stayed with the same colour throughout.

While the dated Fitbit Charge HR could only display a single line of numbers, the Fitbit Charge 2 has an entire screen’s worth of display. Visibility under bright sunlight might be a stretch but as long as you’re indoors it’s unlikely an issue.fitbit charge 2-explodedThere’s a single button on the Fitbit Charge 2 which controls all functions along with a display which is “tap”enabled.

Optical heart rate sensors are placed on the back of the Fitbit Charge 2 along with the charging port. The cable to power the fitness tracker is proprietary.fitbit charge 2-feature-1The Fitbit Charge 2 is merely splash proof so while it may survive your perspiration, it won’t hold up in water based activities such as swimming, diving and so on. A pity since the lower priced Fitbit Flex 2 is already swim proof.

Battery life is listed as up to 5 days but I managed 4. Again this will depend on frequency of smart notifications, activity tracking sessions and whether the heart rate monitoring is switched off or put on auto mode.


Wrist Based Heart Rate

The Fitbit Charge 2 was compared versus a Polar H7 chest strap heart rate monitor. The workout consists of a 5 minutes warm up, followed by about 30 minutes of interval on an elliptical machine followed by 5 minutes of warm down. The entire workout lasted about 40 minutes.fitbit charge 2-hrSince there isn’t an official function to download the HR data in non GPS mode, I had to take a screen shot of my HR graph as listed on the Fitbit web platform before superimposing it on the Polar H7 HR graph as plotted by Microsoft Excel.

Other than mild tweaking of the aspect ratio, the HR graph from Fitbit was left unmodified.

With regard to the accuracy, I did notice that the readings are usually in the same range as compared to a chest worn HRM during the work out; save for the initial flat liner.

In workout mode, heart rate is sampled once every second. In all other conditions, heart rate sampling rate is once per 5 seconds which is pretty decent considering the Apple Watch and some Garmin trackers sample all day heart rate only once every few minutes.fitbit charge 2-hr_hrYou can also access the current heart rate reading right from the fitness tracker. The heart rate monitoring turns off automatically when the fitness device senses that it’s not being worn.

All Day Activity Tracker

fitbit-mobile-appThe is where the strength of the Fitbit series of trackers lie. The Fitbit Charge 2 does the essentials of daily activity tracking very well. For example, your steps, calories, floors climed, distance, activity minutes, and hourly activity are all recorded and accessible from the mobile app.

Sleep tracking is automatic but the stats are only accessible from the Fitbit mobile app.


When activated, the user will receive guided information to inhale and exhale for either 2 or 5 minutes. While the feature is neat, i thought it’s counter intuitive to have to look at the display in order to follow the breathing duration.fitbit charge 2-breathingFor example for a full 2-5 minutes, my arm has to be lifted to my eye level or my head has to look down at the Fitbit Charge 2; both options hardly aid the ergonomics of breathing.

Like Apple Watch Series 2 the Fitbit Charge 2 also uses vibration to guide the user in the breathing exercise. This feature came with an update on 22nd December 2016. Previously, there wasn’t any vibration for this feature.


To commence exercise tracking, simply ensure the exercise event you wish to engage in is on the Fitbit Charge 2 by customising it from the mobile app.

Select the event by long pressing and the workout session is being tracked. Long press again to stop tracking.fitbit charge 2-workout-viewDuring exercise tracking, the stats that appear on the display depends on the exercise and it isn’t customisable. So you’ll get distance when you choose running as an activity but you won’t see distance when weight-lifting.

When activities such as running and biking are selected, the Fitbit Charge 2 will tether on the connected mobile device’s GPS and display stats such as pace and distance. When you choose GPS required activities such as running but without the presence of the connected mobile devices, the distance and pace will be accelerometer estimated.fitbit charge 2-workout-appThe stats of the tracked workout session is then accessible on the mobile app or on the Fitbit web platform.

Cardio Fitness Level

Fitbit automatically provides you with a Cardio Fitness Level based on your resting heart rate and user profile. In my case, I was getting a score of 51-55.

For comparison, my VO2 max as estimated on the Garmin Forerunner 735XT  was 52 and my Polar Running Index score was 52. It’s all within the same range.fitbit charge 2-cardio-fitness-levelYou can obtain a more precise Cardio Fitness Score & Level by going for a run of at least 10 minutes with your mobile device’s Connected GPS. The higher your Cardio Fitness Score, the better your cardiovascular fitness.

Smart Notifications

The Fitbit Charge 2 is capable of displaying calls, text messages and calender events. If the messages are too long, it’ll be truncated.


Fitbit’s mobile app is the epitome of fitness tracking stat presentation for now. It’s concise, easy to use and is particularly strong in the social front where addition of friends who are on the Fitbit ecosystem is easy.

There’s also a web platform where the data can be viewed more clearly. A premium upgrade gives you access for benchmarking versus other Fitbit users.

There’s been requests for users to download their all day heart rate and heart rate during activities which Fitbit has yet to implement for its heart rate enabled fitness devices.

Over the years, Fitbit has also added novel features such as Challenges and Adventures, all in the name of enhancing the user experience when fitness tracking.


Silent alarm and Stopwatch

fitbit charge 2-stopwatchYou can also set silent alarms for the Fitbit Charge 2 but this has to be done from the mobile device.  Also there’s a stopwatch function right in the Charge 2 fitness tracker.


The Fitbit Charge 2 automatically recognises select exercises such as, biking, sports, walking and more and will log these activities so you won’t miss out on every single morsel of activity.

It’s pretty accurate in automatically detecting periods of physical activity. I can’t say the same about the correct identification of the type physical activity.


fitbit charge 2-feature-1I understand there are users who are more concerned with all day activity tracking experience and are fine with on-demand GPS capability through connected mobile devices. But there’s no denying that the lack of GPS on the Fitbit Charge 2 made the fitness tracker appear somewhat lackluster compared to recent released such as the Forerunner 35 and the Polar M200. The water resistant rating is another downer.

The saving grace is the Cardio Fitness Level index, the enlarged display and the changeable wrist straps.

Fitbit’s devices have always been strong on the all day activity tracking front. The company focuses on improving the activity tracking experience, upgrades with a few novel features, allows for aesthtic customisation.

Going forward, I’m unsure if Fitbit’s modus operandi is sufficient for the company to maintain their placing as the top dog of wearable fitness devices.

For comparison, Polar’s M200 is retailing at the same price of the Fitbit Charge 2 and has GPS along with mobile app notifications. Huawei’s Fit smartwatch at just $129.95, lacks GPS but provides physiological measurements powered by FirstBeat.

Personally, I thought the Fitbit Charge 2 is a premium representation of Fitbit’s tradition. There’s a lack of innovation other than hardware improvements but it’s a safe buy nonetheless. After all familiarity is comfort isn’t it?

You can purchase the Fitbit Charge 2 at $149.95 from Amazon where there’s usually a small discount, great return policy, and free delivery depending on where you reside. In return your purchase helps to offset the costs associated with the running of this site. Thanks for reading!

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