For the past three weeks, I’ve been wearing the new Fitbit Flex, a new competitor in the health wristband market. As a former unofficial beta tester of the original Jawbone Up, I was excited to start using a new wristband to track my steps and sleep. With great battery life promised and a sleek design, I had high expectations. Did Fitbit pull it off? Read on to see my full review:

Inside the box

simple.b-dis-png.hb2e6b2f595017592d180390ef6ebf2f6The Fitbit Flex box comes with a USB charger to juice up the battery, a USB wireless syncing dongle to update the grab the information from the device, the Flex itself, and two rubbery wristbands – small and large. The included wristbands should fit most users (and have many adjustment positions like a belt), but other sizes are available from their online store.

Rather than the Flex being part of the wristband, it’s actually a black device that fits right inside. This makes it less expensive to change colors – in fact, you can change colors every day to match your outfit. Yet, I find this intelligent design to be flawed. The cavity where the Flex fits in has room for water to enter. While the device is water-resistent (not water proof, meaning you can shower with it but can’t go deep under water where there is pressure), I have given up on showering with the Flex since water enters the band and slowly drains out throughout the day and makes a funny squishy noise until all of the water is gone. I also clean out the inside cavity every few days to make sure sweat doesn’t add up and start smelling.

Fitbit app

The Flex, just like its sister products like the One, Zip, and Aria Wi-Fi Smart Scale, syncs to the free Fitbit app. The Flex syncs wirelessly over Bluetooth 4.0 every 15 minutes (and can be forced to sync at any time). The device sends over steps, distance walked, and sleep. In addition, you can use the application to keep tabs on your water consumption, calories burned, weight, activity, food, and even keep tabs on your friends.

Sadly, there are no reminders asking for you to input the information. In addition, if you haven’t logged water consumption for many days, there is no dramatic push notification asking if you’re dehydrated and requesting that you drink immediately. This is definitely the killer for the Fitbit ecosystem – it depends on your own self-motivation, rather than acting as a personal trainer always pushing you to watch your weight or drink the necessary amount of water every day. While some may find that to be too pushy, the option to be pushed to eat the right amount and find more time to sleep would be the next step in health-related smart devices.

How it works

Once you’ve put the band on, you can double tap the wristband and it’ll display LED lights. There are five LED lights total, representing the progress towards your stepping goal for the day. If you’ve set the walking goal for 10,000 steps a day and have walked less than 2,000 steps today, only one LED will appear. Beyond 2,000, two LED lights will appear. Once you’ve met your goal, your Fitbit has a fun celebration by vibrating and lighting up all five LEDs.

When you’re ready to go to sleep, you tap the Flex five times rapidly (this takes a bit of practice since it’s picky). I usually forget to do this, since I always manage to fall asleep in the middle of a Netflix episode. I wish the Fitbit would realize that you were asleep eventually and go into sleep mode. You must also tap five times when you wake up to tell the device that you’re out of your slumber. Once again, I forget to do this so the app will report later that I was trying to sleep yet I was walking around. No, Fitbit, I don’t sleep walk that often! Also, Fitbit doesn’t talk about the five-tap-for-sleep in the setup process, so I had to find out about that by looking it up online.

Battery life

On the Flex specs page, the company says the battery life for the device is 5 days. However, I’ve found that this is an area where the Flex really shines, as I have been charging just about every 7 days. Charging through USB to my computer, it takes just about 90 minutes to go from dead to fully charged. As an added bonus, the app will send a push notification to your phone when the battery is running low so you never miss a step. The battery definitely gets an A+ from me.

My experiences

I had it on a bit too tightly...

I had it on a bit too tightly…

The first few days of having the Flex, I was really excited to type in every single meal, every ounce of water, and I even took extra walks around my apartment complex to meet my daily goals. Over time, I would forget to tell the device that I was going to sleep, I stopped walking (at 11:50pm it’ll still show that I’m under 2,000 steps… oops), and my general usage of the application is definitely lower.

It’s a wonderful device, don’t get me wrong. As compared to the buggy original Jawbone Up, this device is definitely more stable and, from my experiences, tracks steps with an error less than 5%. However, I do long for a more complete “personal trainer” device that bugs me more often. I want the push notifications that tell me to go take a walk. I miss the Up feature that makes the device vibrate if you haven’t walked in a certain interval of time. I want a device that doesn’t make squishy noises after I get out of the shower. For the $99 price point, it’s a wonderful buy for those who are ready to be self-motivated and ready to push themselves to be fit. For me, however, I’ve gone back to my old ways of sitting at my desk for 18 hours a day.


The Fitbit Flex is a sleek device with tight app integration. But it’s “part of a complete breakfast”, you might say. The device itself will not make you fit. If you’re ready to make a change in your lifestyle and you’re prepared to push yourself into the next level of fitness, then this device is definitely for you.

To buy the Flex, check it out on the Fitbit store online. It’s been sold out since it’s launch, so you will have to wait a few weeks if you buy it from their store, Amazon, or Best Buy. I was able to grab it with a local pick-up at Best Buy, so be sure to check the inventory of your local stores.

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