(Update! My Fitbit Charge 2 in-depth review is now available here! So swing over to that page for all the details!)
Fitbit’s starting off the week ahead going into IFA (a big tech show in Berlin later this week) by launching a slew of activity trackers and related activity tracker accessories. Plus, there’s some software updates to be had for existing Fitbit users. Let’s dive right into it.
Fitbit Charge 2:
First up is the new Fitbit Charge 2. This unit sits in the middle of Fitbit’s product line-up, in terms of price and functionality. Whereas you have the Fitbit Flex 2 down below it from a price/functions standpoint, and then the Fitbit Blaze above it. Meanwhile, the Fitbit Alta kinda slots in just below this, but with a slightly different feature set.
The original Fitbit Charge HR had optical HR on the back of it, primarily for 24×7 HR recording, but also the ability to have a basic workout mode. That optical HR sensor is now considered standard on the Fitbit Charge 2, and they’ve expanded the usage of it.
First is that they’re giving you a cardio fitness level score by tracking and trending your daily resting HR and exercise data. This score is essentially your VO2Max score. Fitbit wouldn’t be the first to do VO2Max on optical, but it will be interesting to see what extent these metrics line-up to existing offerings in the market (i.e. Polar, Garmin, a million apps, etc…). I thought the below color categorization of fitness scores was kinda interesting, because for men 30-39, typically you’d take a higher score than 49 to be considered ‘excellent’. Update: Fitbit found an error in their earlier screenshots, and send over updated app screenshots with the correct VO2Max categorizations in them, I’ve swapped out for the correct one below.
Here’s both Ryan Hall and Sarah Hall’s scores (famous world class runners):
In order to soothe you after you find out your fitness score is dismal, the company is introducing a new guided breathing sessions functionality into the Charge 2. The unit will guide you through two and five minute sessions that displays real-time HR fluctuations and breathing (essentially heart rate variability) via an animated wave icon, and then gives you vibration cues alongside animations to calm you down.
These sessions are based on your current rate of breathing, rather than being canned. So it’s a bit more customized to that exact moment.
Speaking of animations, the unit features animations in many areas, such as the new sport modes. Previously the Charge HR only had a single sport mode (aka ‘sport mode’), now it has numerous modes. For example there’s a bike mode, a running mode, a gym/weights mode, yoga, etc…
Each mode features a mini animated person/icon of that mode, plus a text descriptor. In my case, those descriptors were in French. But, Vélo sounds cooler than ‘Bike’ anyway.
The unit also features an interval workout mode, which is the first time we’ve seen that at the lower end (the Blaze includes a variant of that). Also of note is that the Charge 2 includes SmartTrack, which is Fitbit’s automatic exercise recognition feature that tracks certain sports automatically – such as running, walking, and elliptical usage.
Next, the unit now includes ‘Connected GPS’, which means it doesn’t include any GPS at all. Instead, that’s the confusingly accurate marketing term that Fitbit uses to mean that it leverages your phone’s GPS for GPS data. Meaning, you have to take your phone. Of course, at this price point and size, you wouldn’t necessarily expect GPS included. So in a sense it’s nice that the option is there if you take your phone with you during your run/ride/etc…
Also of note is that the Connected GPS will auto-calibrate your stride length on the device, so future runs sans-GPS are more accurate. This can also be done manually too.
The Charge 2 will be available for order today on Fitbit.com, and tomorrow everywhere else. Shipping will be in ‘September’. It’ll run you $149USD with your choice of black, blue, plum, or teal bands. Yes, plum. No peach. They are also offering additional textures at $179 (including rose gold and ‘gun metal’), which includes the tracker.
Fitbit Flex 2:
Next we’ve got the Flex 2. This unit is more of the minimalist Fitbit, being that it doesn’t have a fancy display – or any display at all. Instead it uses five small LED’s to give you feedback such as move reminders and progress towards your daily step goal. Plus, it’ll illuminate when text messages or phone calls come in.
The unit has seen a 30% reduction in wrist real-estate square inches compared to the previous version. But more important than that, the thing is the first Fitbit product to actually be waterproof. @#$# finally. The unit is waterproof to 50m of depth, so you can go swimming all day long. And in fact, the unit will track your pool swim including laps, duration, and calories burned.
For the most part, the Flex 2 is about having a hardware offering that feeds into the greater Fitbit ecosystem. So the unit is minimalist in terms of hardware, but behind the scenes you’re still getting the same Fitbit platform as other units.
As with many new products from Fitbit, the unit has more fashion-oriented accessories. In particular, these three bands: 22-karate plated rose gold stainless steel, 22k plated gold, and regular stainless steel.
These bits of jewelry open up like a clam shell and allow you to pop the Flex 2 pod inside of it:
There’s also a necklace option too. And on top of that they’ll be doing three additional fashion lineups for the Flex 2, including ones from Vera Wang and Tory Burch, as well as something called ‘Public School’, which they say is designed to be aimed at frequent Tinder users. Actually, they didn’t say that. Officially they said “urban street-style looks for approachable luxury accessories in styles that range from high-end bracelets to accessible sports bands that are both contemporary and sophisticated”. But ya know…same-same.
When it comes to purchasing the Flex 2, it’ll set you back $99 for the base unit in either black, magenta, navy, or lavender. Alternatively, you can pickup bands from $14 for the classic bands, $89-$99 for the bangles (Guys note: Disappointingly different than bagels), and $79-$99 for the pendants. Availability is pre-sales on Fitbit’s site today, and everywhere else on earth tomorrow at midnight. But shipping for this won’t happen till October.
Some Gold Alta Bling:
Next, the Fitbit Alta (which was released earlier in the year) is receiving some hardware accessories, specifically, golden hard accessories. They’re rolling out a few different variants of gold bangle accessories, stainless steel bangle accessories, and then a straight-up gold Alta. All of which are 22-karat gold-plated.
The complete golden-child Alta:
Or the gold Alta with the regular black sport band:
And there’s also a stainless steel band too.
Finally, some activity trackers that I can do product shots on the exact same table as I do wedding cake shots for The Girl and the Cake Studio.
Fitbit Blaze Upgrades:
Finally, last but not least, the Fitbit Blaze is getting three updates – two of which add features that the rest of the market has had for a few years: Smartphone notifications and move reminders.
Yup, previously the Fitbit Blaze (like all Fitbit products) only would display phone, text, and calendar notifications. Despite its gloriously pretty screen you couldn’t see notifications from Snapchat, Twitter, or Facebook. Rather, only the core three: Text, phone, calendars. With this new (and free) software update, you’ll now get any smartphone notifications that your phone can throw at it. Boom!
Next, you’ll now get move (inactivity) reminders on the Blaze. This will remind you each hour to move, if you’ve failed to get your move on. In total you’ll need to throw down about 250 steps per hour.
Finally on the software front, you’ll get some new clock faces (aka watch faces). Five new faces to be precise, giving you nine watch faces in total.
Lastly, for hardware, they went ahead and gave you a new golden Blaze edition, which you can pickup for $229, or $99 for the accessory band. Plus some new straps including khaki and olive, as well as a thinner (in width) leather band).
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With that – thanks for reading all! Feel free to drop any questions below. My understanding is that the new units for review are working their way towards me as we speak.
Update: You can now pre-order the Fitbit Flex 2 and Fitbit Charge 2 on Clever Training. In doing so you not only support the site here, but also save yourself 10% using DCR Coupon Code DCR10BTF. Plus, free US shipping!
Will the new Charge 2 also support swimming? I would love if I could get SWOLF score from it!
I wouldn’t think so – the Charge 2 isn’t waterproof/resistant. Only the Flex 2 is made for swimming/showers, etc…
Ray,
Is the Blaze getting the VO2max “cardio fitness” stuff as well?
Thanks,
Matt
You did not mention it, but does Charge 2 support the same notifications as the updated Blaze firmware?
It appears they went with Phone/Text/Calendar alerts on the Charge 2. They upped the Blaze’s notifications because, well, if they didn’t, there would be almost no reason to buy a Blaze over a Charge 2.
Have you heard anything about the wearable Tomtom has been teasing?
I would assume it’s some sort of “advanced optical HR analysis” aka VO2Max-ish.
Will this new vo2 functionality be available to older devices? It doesn’t sound like the optical hardware is significantly different and its all calculated on their servers from collected data. Which would mean we could see it on the fitbit dashboard.
Interested in this too, I’m guessing a lot of people will be!
Ryan Hall is not the U.S. record holder in the marathon. Khalid Khannouchi is.
“Ryan Hall (born October 14, 1982 in Kirkland, Washington)[2] is a retired American long-distance runner who holds the U.S. record in the half marathon. With his half marathon record time (59:43), he became the first U.S. runner to break the one-hour barrier in the event.[3] He is also the only American to run a sub-2:05 marathon (2:04:58 at the 2011 Boston marathon). However, this time is not eligible to be a record due to wind-assistance the course being point-to-point. “
Record eligible courses have to have a start and finish that are no more than 50% of the race distance apart, and the decline can be no more than .1%. Boston fails on both counts. There’s no “wind assistance” rule, though there was a massive gale at his back in 2011.
Well, dude is still REALLY FAST.
Good lord. Some people
I’m a bit sensitive to the issue because people frequently claim that Ryan Hall is the American record holder on the grounds that the immigrant Khalid isn’t a “real American.”
Ray… some updates:
1) The gunmetal and gold editions of the Charge 2 at $179 are not an accessory, they include the tracker so it is just a $30 premium to get a “body” of the tracker to have either a gunmetal or gold finish vs. the silver on the normal tracker. They also include rubber straps that have a texture unique to those models but nothing special in terms of material. Both are not shipping with no date yet.
2) The Charge 2 is shipping September 1st in Australia and September 6-8 in the rest of the world (about a week) but only for certain band colors. Some of the alternative band color models for sale are listing dates in October.
3) The Flex 2 is shipping at the END of September for some band colors and the END of October for the other colors so its about 3-4 weeks out at best.
4) The Flex 2 is claiming to support some kind of lap or stroke counting while swimming which should be interesting.
My thoughts…
A) I hope VO2 Max support is added to data derived from ANY Fitbit with optical HR, at least if you also own a Charge 2! I use Surge for all my runs and even some 24×7 periods during the week with Charge HR for the rest… I hope the data will blend.
B) The Surge is now the odd product out. Still beset with the design issues of the last generation that cause high wear and tear and frequent need for Fitbit to replace them I can’t imagine the design is long for this world. I hope Fitbit plans a “Surge 2” or at least a Blaze with integrated GPS / waterproof in the near future and if you have any contacts their I would love if you could ask about their commitment to the Surge line. I am concerned they may just drop it and go with Blaze / Charge 2 and their “connected GPS” model.
Thanks David, just finished re-clarifying accessory sections.
Does the Charge 2 support music controls (Spotify) easily during runs?
Charge 2 does not support music control. Only the Fitbit Blaze and Fitbit Surge support music control.
Thanks.
That is very very unfortunate and a personal deal breaker.
Hi Ray,
It looks to me the Charge 2 is a little slimmer than the Charge HR. Is that correct ?
Thanks !
The new Charge 2 is actually 0.01 wider than the Charge HR for sure but it appears less tall/thick than the Charge HR (at least at the asymmetric highest portion of the old band.) I can’t confirm that last part though. Several reviewers have said it feels smaller but regardless I think it is pretty darn close, don’t expect vast differences.
Thanks David ! I have the same impression about the thickness.
Now if they only made a device that is actualy built to last, say, more then a year.
To be fair, they happily replace a product even after warranty expired. One of the highest hardware fault rates I have seen but maybe the best customer service.
They do that to keep user from going to another brand. They spend so much money on RMA’s and repairs I don’t know how they stay profitable.
Of course. That’s why companies do customer service, to keep users from running away. Just saying that Fitbit do it well. On the profit point, when Xiaomi sells a band with the Flex functionality for $10 while Fitbit asks for $99, it’s kind of clear that a large chunk of the difference goes to fund customer service (and the other part to develop Fitbit platform, which is still by far best of breed for 24/7 activity tracking).
I agree, but I already had three replaced. I don’t live in the US, it costs me to send back and again the shipping amd taxes for the replaced product. The local retailes don’t have the same customer service and have refused to replace it.
Interesting, I was never asked to send the defective unit back and always got the replacement shipped from a hub so that import fees didn’t apply (Australia and EU). Replaced four, too. Which, I admit, sounds ridiculous :-)
My Fitbit charge hr died last night after 13 months of daily showers. Just in time for a new one!
Typo:
“I thought the below color categorization of fitness scores was kinda interesting, because for men 30-39, typically you’d take a higher score than 49 to be considered ‘excellent’.”
Should read “…491 to be considered ‘excellent’.” to be correct?
Scratch that. Ugh.
I count 5 LEDs on the Flex 2, not 4.
Can it display running pace after auto-calibration and is that any accurate? Thanks!
i was excited when i saw this as i hoped they might have done something to improve on the resting heart rate “feature” of the charge hr. sort of the case in that they’ve confused the matter even further by adding other stuff into the “score” but it sounds like the basic RHR is still the usual fitbit unreliable random number several bpm higher than commonly seen actual HR readings from the unit itself.
i was also hoping the charge 2 might have improved sleep detection but it seems not.
re the comments around fitbit’s support – yes they’re quite happy to give away product (probably indicative of the actual manufacturing cost) but in my experience they’re completely unwilling/unable to provide any actual support/resolution of issues.
i just want a device to track my recovery based on RHR and sleep but have found the charge hr to give RHR values that bear no resemblance to my actual state of fatigue and the sleep tracker thinks i’m asleep if i relax in front of the tv so i have to manually update it half the time. i’d ditch fitbit completely if it wasn’t for the fact i also have their scales so am kindof tied into their platform…
Interesting comments on RHR which is primarily why i’m looking at one of these. Any suggestions as to a device that better tracks RHR?
Not trying to push FitBit, but with just a bit of effort it’s not that tough to get true RHR. Looking at the “dashboard” display of heart rate, on PC screen at least, it plots HR every 5 minutes with values displayed as you drag cursor along time graph so you can choose if you want only waking RHR or include sleep as well. And you can scroll way back in time too. It’s just not displayed as neatly and you would have to log it somewhere else to plot it.
yeah, just that it defeats the point of having a connected device that supposedly records your RHR for you.
@Brent i went fitbit as Ray noted that garmins “smart” hr recording samples very little at rest so inherently gets poor rhr quality. fitbit records hr at rest nicely, they just try their own smarts in interpreting those hr values.
FWIW this is the best i cold get out of them:
“While we are unable to provide you with additional details in regards to how resting heart rate is calculated, we do want you to keep in mind that it is intended to be an estimate. Your resting heart rate is usually higher than your heart rate while you are asleep, so as mentioned, your resting heart rate can be higher than the lowest number that you see in your heart rate graphs.”
– still missing the point i made that the RHR they calculated was frequently higher than my awake HR lows, let alone my sleeping HR. i know i’m not the only one to have experienced this, seems relatively common, possibly “normal”.
as i said, i don’t really actually care what the RHR number is, as long as it goes up and down appropriately as my fatigue/stress levels change. my experience is that it has not done so but that may or may not be true for others. to be fair, i do potentially have some odd things happening with my RHR due to a thyroid issue…
it may or may not be a useful metric but its certainly not RHR as its normally known – its kindof like this new “cardio fitness level score” vs VO2Max – some sort of proprietary fitbit calculation intended to achieve the same purpose which may or may not actually do so.
if you haven’t already, read Ray’s post around this link to dcrainmaker.com
Don’t see mention of ‘get active’ alert on Charge 2 though would expect it. Wonder if they are just keeping it off to give reason to buy Alta or Blaze or whichever have it.
On Fitbit’s website comparison chart, they don’t have option to show Charge HR. I wish it was still there to make it easier to see what Charge 2 has over Charge HR.
I see via the PCMag review that the Charge 2 does have activity alert. Perhaps Ray says so also and I just missed it.
My understanding is that it does (I don’t have the unit handy at the moment).
I’m cautiously skeptical of measurement of breath rate determined by heart rate. I wonder if dashboard will allow tracking of breathing rate as well or if it’s just used for relaxation exercises.
Very nice job! Best regards from Poland ;)
Hi,
Will you test the accuracy of HR monitoring during high intensisty trainning. ?
Do you expect it to better than the Charge HR as the sensor is bigger ?
Thank you for your post !
Marc.
Yes, definitely something I’ll test.
Good news, so I can choose between the Charge 2 and a classic chest belt device to replace my Polar RC3 GPS which after 3 years last only 1 hour and a half before stopping recording my runs :-(
Good to see a slew again. It has been so long I can’t remember the last slew. With turbo season round the corner hopefully there’ll be another slew then :D
Hey Ray, would it be possible for you to upload some pictures of the Charge 2/Flex 2 on The Girl’s wrist? For a time I considered buying the Blaze but aside from its hardware/software shortcomings it was seeing how bulky it was on me that I decided against it, so I would be interested in seeing how the new units look in a thinner wrist. Thank you!
Ray, do you know if they plan to support / display / track HRV? The breathing thing sounds like steps in that direction – it would be a real killer feature for athletes if they made it easy to track HRV with a device you already wear all the time.
Ray, can the Charge 2’s watch face be customized to display 1) Time, Calories Burned, and HR, or 2) Time and Calories Burned?
My main use of activity trackers is to track my calories burned, so it’s a hassle to have to press two buttons every time I want to check my calories burned throughout the day on my Polar A300.
“22-karate plated rose gold…”
Sounds kick-ass! (sorry, couldn’t resist) ;)
On a serious note, I really like Fitbit’s new design direction with the Alta and Charge 2. Makes the products look a lot more stylish.
My only query is with the strap attachment – how secure is it, and is that clip a potential crud-catcher?
Thanks for the early look-see. :)
Ray, does the clasp of the Flex 2 seem to have any improvement over the original? The original seemed to open too easily. I’ve lost at least 1 Flex when it caught on something and sunk in a body of water, and had other numerous close calls when it inadvertently opened.
One of the best Flex accessories I’ve seen comes from RoadID: they have a rubber cuff to hold the bracelet shut, and an ID badge that slips over the bracelet. I wear my Fitbit everyday so I’m glad to not wear 2 things on my wrist. Hope they can come up with a new RoadID for the updated Flex 2 design.
I agree Brad .. stupid design. It has to be about the money .. and why they will give you a new one if you lose it. But it does make a ton of companies that make the Fitbit clasp fixing accessories very very happy.
Hey Ray,
I’m with Matthew B with my question. Will the VO2 max be on the Blaze?
Does it allow you to connect to a chest strap or any external bluetooth device? I like the idea of being able to have this option if I want precise heart rate tracking.
No.
Ray, can the fitbit [platform now interchange their device.. Meaning i can have 2 fitbit device and change between flex and charge and still having the same step on that day?
Yes, it’s been able to for about a year now. :)
My GF and I just bought Alta’s a few weeks ago. Now I’m finding the flex2 much more appealing with the swim-proofing. I also haven’t really cared much for the LED display of the Alta because I don’t look at it ever. Might try to sell mine at the end of Sept once the flex2’s start shipping.
when are these updates for the blaze taking place?? and does the new blaze already have these updates?
Interested in this.
Just bought a Blaze today (from Staples, to replace a Charge HR after trying out Garmin’s Vivosmart HR; had the Charge 2 been available right away, might have gone with that instead). The notifications are still call/text/calendar, after the initial firmware update. Other notifications will be useful. Not that they fully justify the price difference with the Charge 2, but it’ll be a welcome part of the whole package.
Ha! So timely…
The update is being pushed today.
link to help.fitbit.com
The thlot pickens…
link to community.fitbit.com
AFAICT… They had pushed the Fitbit Blaze 17.8.301.4 firmware update (with new clock faces, extended notifications, and activity reminders) to 5% of Blaze owners, as something between a progressive rollout and a kind of beta. Though information was posted in their community forums (and their community managers are working quite actively in these forums), some details were quite fuzzy and people were confused and/or upset. To this day, there are conflicting bits of information between some product pages, in terms of which of these features are currently available.
Sounds like Fitbit reverted the new clock faces after the initial rollout. But those clock faces are back in yesterday’s 17.8.301.7 firmware update.
Part of the issue may be that there’s no clear way in the app to search for updates or to get information about what’s coming. It probably doesn’t matter in most cases, but this is one situation in which the update brings enough feature improvements that it may have affected some people’s purchasing decisions (certainly had a significant part in mine). There have been similar situations in the past with the Charge HR, for instance, which Ray had also described. One might even say that Fitbit is pretty good at adding desirable functionality through firmware updates. But the rollout process could be improved.
The thing that amazes me about Fitbit is that they never learn. The terrible and so awkward push together clasp system .. like how many times can you possibly lose it ? Guess their poor customers will find out. I think if it saves Fitbit $2 for each one compared to a proper strap .. they can afford to give those that do lose them a new one. But still a stupid design. At least Garmin eventually learned.
Still had $15 from ordering the Fenix 2 HR and with the 10% off coupon code came out to $129.95 :) The gift that keeps on giving! I don’t trust the Fenix HR for calories, I don’t think I burned 2774 calories with one hour of Bodypump when my base burn is 1950 and I barely moved today (other than class and taking the puppy to the vet in the car).
I preordered the Charge 2 on Amazon for $114. Now received it and I am comparing it to the FR235. I have the FR235 on my left wrist and the Charge 2 on my right. Note that I’m right handed. My initial impressions of the Charge 2 is that its pretty good. I like the better sleep tracking. The Fitbit App is also better and easier to use. Did a quick 10 minute run last night and the Charge 2 seemed to be able to track my HR better than the FR235. There were hardly and breaks or jumps in the recording. The GPS (Phone) also seems to track better. Will need to test more. Couple things to note though. The Charge 2 is consistently 400+ steps above the FR235. I feel that the FR235 is way more accurate on the steps. Example, I just had just woken up and went through the morning routine. The FR235 recorded about 50 or so. The Charge 2 was already in the mid 100 range. Another thing is that I think the Charge 2 is way over estimating my VO2 max. It says 69, while the FR235 says 57. Im inclined the trust the FR235 more. Im not a super athlete. :D
Oh and another thing, Im so used to the FR235 being constantly on. It is annoying to have to constantly flip my wrist for the Charge 2 to display.
Hoping you’ll get a Charge 2 soon to test–my wife just returned her Charge HR because it was so crappy tracking HR during exercise and she’s hoping this will be better. Lots of reviews on Amazon but no one talking about that aspect.
Of note: link to twitter.com
@Savesee: I don’t have a Charge 2 but it sound like it’s the exact same “Pure Pulse” HR system as the Charge 2, though I guess the same HR system performance can vary somewhat depending on device.
Thanks Ray for all the great reviews!
I am looking for a nice wristband for my girl. The Garmin Vivosmart HR (+) was my sure favorite until I saw this review about the Charge 2. I am in the Garmin universe (Run, Bike, Weight, Cloud, Community), but not Fitbit. I am wondering what would be your preference over the two? The Charge 2 seems to me just a bit more adequate for the average user…and it seems to be prettier, which is important for girls…Does Fitbit offer an offline data collection, or is, like Garmin, everything uploaded to the cloud? (Not so important to me, but for the girl.)
Chris
To answer your specific question about offline data, yes, everything is uploaded to the cloud (some consider data as the new oil and it wouldn’t be surprising if those companies’ business models made more room for data collection, in the near future). In fact, you can only sync some of the data from your tracker, if you’re completely offline. In the Fitbit case, there can be some neat benefits, especially with the 50$/yr Premium account.
Now, as to which band to get… It’s a remarkably difficult question, unless you have a very good reason to go with a specific model. Been agonizing over this for a while.
Just spent a month with the Vivosmart HR after spending over a year on the Charge HR. Eventually bought a Blaze, yesterday. Very happy with that purchase.
You can weigh the pros and cons of all of the trackers available. If your girl swims, the Vivosmart HR is a pretty good option. If she runs, the HR+ is even better. If smartphone notifications could improve her life (hard to assess without trying it), both the Vivosmarts and the Blaze are better bets than the Charge 2. If she cares about entering your “team”, being in the Garmin universe might have some advantages. It’s not too hard to share data by exporting to TCX files (which Fitbit does from its web dashboard, even with the free account). But it’s not the same thing as being on the same system. Fitbit makes it especially easy to engage friends in challenges and such. Been rather ambivalent about this myself, but the presence of several Fitbit users in my social network has been a small part of the reason the Fitbit ecosystem works so well for me.
So, there’s already a lot to be said about specs.
But, as you say, looks can be pretty important for such an accessory. The Blaze and Charge 2 both allow for customization but the Blaze might be too bulky (“chunky” sounds fitting, to me) for most people. The Charge HR was pretty neutral but not customizable. The Charge 2 is a bit prettier with the added bonus of allowing for changing wristbands. The Vivosmart HR isn’t too conspicuous, but it’s clearly not a fashion accessory either.
Another thing which hasn’t been discussed much is the differences between the displays. While the Vivosmart HR’s always-on display has some advantages when you just want to look at time, it’s been quite a bit harder to read in low light or without glasses (say, during exercise) than any of my Fitbit trackers. The Blaze’s display is really, really nice. Easy to read key info, even in bright light (time, heart rate, and steps). The Charge 2 does have an improved display over the Charge HR, but it’s mostly a bigger version of the same type of display.
To make things even more difficult, there are other trackers coming out. For instance, Pebble will soon release to its Kickstarter backers a version of its smartwatch which adds optical HR. Details are a bit scarce as to how that’ll measure up (including in refresh rates), but it’s also something to consider.
All this to say, it’s difficult to choose the ideal device. These things are so personal that much of it is deeply subjective (how the thing feels on your wrist, for instance) or contextual (how many of your friends use a certain platform…).
In your girl’s case, it might be a matter of letting her decide. Or buy her something from a store with an excellent return policy.
When do you intend to do a review of the Swim tracking capabilities of the Flex 2? thanks