Fitbit Flex vs. One Review

luckydays27

I recently bought the Fitbit Flex and the One to do a side by side comparison to decide which device was going to work best for me. I will admit that my preference was skewed to the Flex as I am less likely to lose the device (or put it in the wash) as I am with the One.

The lack of display is not a factor to me as I set the status lights on the Flex to display my calories burned as that is the goal I am most interested in seeing. It breaks your goal up into 5 increments and when you reach 1/5 of the goal the first light appears when the face is tapped twice and so forth. This was enough for me. I could always log on to fitbit to get true data points when ever I was near my computer.

I wore both devices for 7 days and planned on a 10 day trial period. At various times each day I would sync both devices to the website to compare data. I found that in most situations, the Flex over calculates the steps taken and therefore over calculates the calories burned for the way I would use the device.

I wore the Flex on my left (non dominant) wrist and the One clipped to my bra in the center. I calibrated each device with my walking stride length. I used all day everyday in all types of conditions. Sometimes I would keep the flex in my pocket by mistake after washing my hands or some other time that I would take it off.

I discovered when used during exercise (worn on the wrist or in my pocket), the devices were comparable in numbers (cals burned, distance traveled, and steps taken). At least the numbers came out close enough to each other that it was acceptable to me. Also, the Flex would be close to the One when the device was in my pocket during non exercise times.

When I wore the Flex on my wrist, while carrying a purse or other item the Flex would calculate more steps than the One. It would over estimate my mileage walked each day as well.

As an example, yesterday I walked 3.5 miles according to my calculations of where I traveled. I was leisurely walking with my purse in my hand. Sometimes in my left hand, sometimes in my right. I was talking on the phone while walking as well.
My data points for this day are:
One - 11:30 am
3.5 miles
Burned 1251 from midnight to the time I synced the devices
Walked 7955 steps.

Flex - 11;30 am
4.25 miles
Burned 1545 cals for the same time frame
Walked 10295.

I then took a 1.5 mile walk without carrying my purses or using the phone.The data from this information is comparable between the devices. My data points were:
One - 1:30 pm
5 miles
Burned 1557 from midnight to the time I synced the devices
Walked 11672 steps.

Flex - 1;30 pm
5.75 miles
Burned 1860 cals for the same time frame
Walked 13347.

I did a workout session at the gym ended the day with the following figures:
One - 9:30 pm
6.75 miles
Burned 2765 from midnight to the time I synced the devices
Walked 16105 steps.

Flex - 9;30 pm
7.5 miles
Burned 3126 cals for the same time frame
Walked 18370 steps

I thought this was an anomaly and was going to give it another try today but this afternoon, I was sitting with a friend when I did a sync of both devices to see where things were for the day. There was the discrepancy between the numbers but until I get do more testing, I could not give up on the Flex altogether. However, after talking with my friend for 30 mins, I did another sync of both devices. The Flex was 200 steps higher than the previous sync. The One however had not changed. And it should not have as I did not get on my feet one single time in that 30 mins. I did not move from the chair I was sitting on except for the fact that I was talking and therefore using my hands as part of the conversation.

The Flex calculated my hand gestures as steps and thus had my counts way off. It is my belief that the flex over estimates the steps and cals burned when carrying stuff in your hands or excessively moving the arm that the device is attached to.

I immediately took off the Flex and will be returning it once I get time to go back to Best Buy. Its not the right device for me. If I wanted to be more accurate and stay in my pocket, the One is that device.

If I were a man or a woman who does not carry a purse then maybe the device is more accurate but since I nearly always have a handbag, the Flex is not going to give me an accurate read out.

Both devices are able to measure your activities and give you the cals burned estimate. But unless the device is accurately giving the info sought, it is not going to help in the weight loss plan I am trying to achieve.

Conclusion - the Fitbit One is the device I will keep and will have to do my best to make sure I transfer it from my clothes and make sure it does not get washed. I feel that it accurately gave me the information I was seeking.

I hope this helps someone who may be on the fence about which model to buy.

niks514

Thank you for this post!! I had told my husband I wanted the flex for my birthday last week and I admit I was a little disappointed when I opened my gift and found he had bought me the fitbit one --- he said he researched and found the one to be much better in most reviews and decided to get me that one -- and I LOVE it!! You post just makes me feel better with my gift!!

SuperStepper408

Thanks for this post. I've been trying to decide which one to buy and what the differences are since I know very little about HRM's. I think you explained it quite clearly and now I will get the Fitbit One instead of the Flex.

FitFunFabulousNicole

Wow! This post came at a perfect time for me - Thanks for the comparison

AliandTrev

Thanks for that, I was wondering about the Flex. Thinking mainly that I wouldn't throw it in the washer as easily. I have know washed my FitBit One twice now and luckily it has remained unharmed by that. It did however calculate that I climbed 10 flights of stairs yesterday after it's ride in the washer/dryer.

GeekAmour

Thank you for this post!! I had told my husband I wanted the flex for my birthday last week and I admit I was a little disappointed when I opened my gift and found he had bought me the fitbit one --- he said he researched and found the one to be much better in most reviews and decided to get me that one -- and I LOVE it!! You post just makes me feel better with my gift!!

Big ups to hubby for doing some research! I luff my one, too.

kristafb

I was waiting for the Flex to come out but got impatient (as I usually do lol) and bought the FB one & I love it!! Thanks for the review!

alisonsurf

Thanks for th review! I was feeling regret that i didn't wait to get the flex especially since I had so many troubles with the first fitbit (they sent a new one!). :happy:

jezama77

Thanks for this post. I've been trying to decide which one to buy and what the differences are since I know very little about HRM's. I think you explained it quite clearly and now I will get the Fitbit One instead of the Flex.

Neither device is a heart rate monitor. Both are high tech pedometers with a few extra features. I have researched a TON of these type devices. I have decided to do more research and get a heart rate monitor, but I might wait a bit and get an amiigo since these actually seem to measure more than just steps...

Here is the link: http://www.indiegogo.com/projects/amiigo-fitness-bracelet-for-iphone-and-android

donnaleighh

Awesome review ..... you might find this one interesting as it also compares One with Flex and it looks pretty consistent with your own analysis

http://www.gizmodo.com.au/2013/05/fitbit-flex-review-peer-pressure-sucks/

hannah0419

Lucky Days- Thanks for the review… I have had the fitbit ultra for about 2 years and the Flex is now on it's way in the mail to me. Your review is troublesome; I was so looking forward to the flex. I really appreciate the work and research you did.

One question: Did you have any trouble setting up a 2nd device to sync? Did you open a new email account or how did you handle that? I plan to use them both for awhile as you did.

Again, thank you.

Hannah

hannah0419

Thanks for that, I was wondering about the Flex. Thinking mainly that I wouldn't throw it in the washer as easily. I have know washed my FitBit One twice now and luckily it has remained unharmed by that. It did however calculate that I climbed 10 flights of stairs yesterday after it's ride in the washer/dryer.

Allan- I also have washed my fitbit ultra twice (front loading washer) and it is working okay except for flights of stairs. It WAY over calculates how many flights I've done.

Hannah

bellaconfusa

Perfect timing on this post - I'm interested in investing in a fitbit but I didn't know which one to get and how useful it really is.

HappyElizabeth

Thanks! This is really helpful. I've had the Fitbit One for about 6 months and absolutely adore it, but wanted to buy the Flex because I'm a sucker for the latest and greatest of anything. But, really, you've proven to me that I don't need it, and that the One is actually the better unit accuracy wise. I've never had an issue with losing it - I always keep it on my bra. (FYI - I have worn it with a HRM and since the activity I do is mostly step based, there was almost no difference in calorie burns, so I've stopped wearing the HRM except for cycling)

wmurphy1975

The Fitbit One may be a fine device but I believe the Zip may be their best. After reading this you may feel the same:

http://mandatory-tech.com/2013/05/09/fitbit-zip-the-least-expensive-fitbit-may-be-their-best/

luckydays27

You are all welcome. I was to impatient to have someone else do the review and had the extra $ to buy both. (with the knowledge that one of them would be returned).

As an FYI, I use a HRM (Polar FT60) while working out and now leave the Fitbit in my bag. I do it this way because the HRM determines my cals burned as I do a cardio/circuit training mix. The fitbit cant accurately measure my cals burned so I leave it alone for that time. As soon as the workout is over though, I put the fitbit back on. My previous test data with the fitbit on while working out was to determine if the steps taken/cals burned matched each other.

As for how I handled syncing, I started two accounts on Fitbit.com with different email addresses (I have several). The account for the One was synced with MFP and the Flex was on its own. I entered all my info into MFP to sync with the One and manually entered my fitness cals burned on the Flex fitbit account. that is how I was able to keep my data points consistent.

For those that think the Fitbit is a glorified pedometer, I guess you can look at it that way. I dont, I see it as an activity tracker so I can know how many cals i should eat each day based on my activities each day. I have a sedentary job so for the most part I sit all day and dont do much. But I also have appointments and meet clients often so on those days, I am far more active. because I live on that side of laziness, I like having a device that takes my activities and tells me how much I am supposed to eat/how many cals I burned. This makes living my life, the way I do, easier. I think this is the best $90 US I spent on diet/exercise/fitness etc in a really long time.

Good luck to all of you. If you have questions let me know.

Lindasilberlicht

I have the Flex and love it. Returned the One to get it as I kept forgetting to take the One off my bra!! I am also keeping track dually. I believe in wearing my HRM while doing cardio and putting in those calories during that time. I can still wear my Flex (or the One) as you can enter your data manually for the workout time, the FITBIT will readjust what was recorded during that time - so no need to take it off your wrist.

When I sync FB with MFP my manually entered exercise gets moved onto MFP.
I compare the calories that are still available, realizing that FB will show more as it monitors ALL my movements. I don't usually use those but it motivates me to move more!!!

mdmcavoy

Interesting and informative comparison. Thank you very much for posting that.

I agree that the Flex is not terribly accurate, but if you do not need the precision, and if you are not making eating decisions based on the information ("Gee, I've hit my goal, so I can eat extra!"), don't discount the Flex. The Flex wins hands down for convenience. Aside from charging it once a week, I put it on and leave it on (through showers, dishwashing, sleeping). No more leaving your Fitbit clipped to that other garment (the one headed to the washing machine) or having it fall to the floor while adjusting your clothing in the bathroom.

I use my Flex primarily to encourage me to move throughout the day, and to work with MyFitnessPal to give me a ballpark sense of whether, overall, my eating decisions and activity levels are moving me toward my goals. I was surprised to find that the sleep monitoring has become very useful for me, showing a recurring pattern to waking up in the middle of the night that I discovered was due to a neighbor's (noisy) late-night routine (they slammed their car door at around 2:15 a.m. most nights).

(For what it's worth, my Flex is underreports my steps about as much as it overreports them. I spot check periodically out of curiosity by syncing the device, noting the steps on the dashboard, then walking for a distance and counting my steps. I have not done a long-range comparison, nor one as exquisitely detailed!)

Antlady69

Very interesting. I wonder if your results had been different if you had worn the Flex around your ankle? That's what I plan on doing. I always feared that arm movement while being stationary would influence the readings.

Thanks for the review!

777twist

I almost bought the Flex, but then read a lot of reviews saying it was off on it's counts. Since I didn't care to wear it on my wrist, the ONE looked like the best bet.

I love it. It works great. And I do much the same as you, in terms of taking it off and using my HRM for workouts.

It is just a pedometer with some extra features... the main difference being it syncs to an account and does the math for you on your steps, elevation, etc... I'm not knocking it, I love mine. But it's not splitting atoms over here. ;-)

But to be honest... I really love my Heart Rate Monitor. I have the BlueHR by Wahoo, and it works great with my iPhone and Digifit.

Everything I have seems to talk to one another, which really helps so I don't have to enter things multiple times (or sometimes at all).

I do think the calculations that FitBit uses are wrong in the grand scheme of things... because from what I can tell they use a daily average to predict the rest of your day. But I think they should break the day up into sections, and then use those section averages to predict. I can't tell you how many times I have earned extra calories early in the day, only to watch them run down close to zero, to zero or below because I'm not doing jack in the evenings. That's a flaw, and I sent them an email about it. But it's not a deal breaker by any means. Just be aware that if you earn extra calories early in the day, don't eat them all up if you are just going to sit around at night. You may end up going negative if you do that.

lv186000

Good job testing, really appreciate the data and results!