Fitbit Flex Review


One complaint that we have is the fact that the Fitbit Flex requires a proprietary charger. There’s nothing really much to the dongle, as it connects to a USB port or wall outlet to recharge the Flex. Still, there’s that possibility of losing the thing, which is a pain because it’s not a typical microUSB charger – so getting a replacement takes some time.

Battery life is pretty darn good with the Fitbit Flex, since a fully charged battery permits us approximately 5 whole days before it inches close to a critical level. It helps too that the connection is Bluetooth 4.0, so it doesn’t require much juice to transfer data from the Fitbit to a Bluetooth 4.0 equipped smartphone. Also, the wait time for it to juice back up to 100% isn’t too long either. In fact, it pretty much tops off in under 1 hour in our experience.


The Fitbit Flex is good in tracking our motion, but it’s the Fitbit app that really gives us the bigger picture.

Even though it might seem like a simple thing, there’s a lot of tech stuffed inside of the Fitbit Flex. As we already know, it features LED lights, a battery, and a Bluetooth radio, but it also packs along a MEMS 3-axis accelerometer to measure various motion patterns to determine things – such as calories burned, the number of steps taken, distance traveled, and sleep quality.

Indeed, it’s nice that we’re able to quickly glance at our progress thanks to its LED lights, but in order to view the data it’s gathered, we’re required to use Fitbit’s smartphone apps. For the most part, it’s pretty accurate in determining the motion of our steps – thus, counting and adding them to our results. However, we notice that it also records quick hand movements as steps, which is a glaring thing because it contributes to adding false data. Interestingly, there’s a setting that allows us to tell the Fitbit Flex which hand we’re using, our dominant or non-dominant one, so we’re hoping that it’s compensating for false movements as well.

The other part to the Flex is the Fitbit Android and iOS apps, which help us to visualize all of the data it’s gathered. Thankfully, the app is comprehensive and thought out, to the point where we’re given a lot of useful information regarding our level of fitness. Obvious statistical data are all present from the Dashboard, like steps taken, distance traveled, sleep time, and calories burned, but it’s also nice to find secondary fitness tracking categories. Specifically, they include calorie and water consumption.

To better visualize all of the data, the app presents it in a line graph view – so over time, we can see our progression or regression. Needless to say, Fitbit has been hard at work with its mobile apps, but its online portal is also rich with even more information for us to rummage through.


Fitbit has been in the game of making fitness trackers, so they have the experience to deliver quality products to the table – and the Fitbit Flex is undoubtedly one of them! It’s stylish, yet discrete, so it’s wonderful that it’s something we can wear and not constantly have to fiddle around with it. Quite simply, it does all the tracking on its own – with minimal interaction from our part.

Sporting a sticker price of $100 right now, it’s an affordable option that gives us the data and tools to better gauge our level of fitness. So will it help us to lose weight? Well, we’re not going to come out straight and guarantee that it will, but rather, we’ll say that it’s a fantastic accessory that complements any lifestyle. Even though it’s going to be seeing some heated competition very soon, the Fitbit Flex is really setting the pace for everything else.


  • It has a very minimalist design
  • Water resistant
  • Available in a variety of colors
  • Mobile app is extremely comprehensive


  • Proprietary charging port
  • Misinterprets hand movements as steps sometimes

PhoneArena Rating:


Latest Stories

This copy is for your personal, non-commercial use only. You can order presentation-ready copies for distribution to your colleagues, clients or customers at or use the Reprints & Permissions tool that appears at the bottom of each web page. Visit for samples and additional information.
FCC OKs Cingular's purchase of AT&T Wireless