AmazFit T-Rex 3 In-Depth Review: What’s the Catch?

The AmazFit T-Rex 3 has garnered much attention over the past few months since its announcement. In many ways, that attention is deserved, albeit a wee bit overstated. Still, the watch has been on my wrist now non-stop for 35 days, putting in nearly 700 kilometers of workouts across cycling (road, MTB, gravel), running, hiking, openwater swimming, and more. I’ve figured out what it does really well (battery life), what it does really badly (clarity), and what it’s so-so at (navigation). Of course, those are just a few examples, I’ve got countless more in each category.

That said, it’s important to understand context here. The AmazFit T-Rex 3 is normally $279, but was recently on holiday sales for $235. At either price, it’s super appealing. Some have tried to call it a ‘Fenix Killer’. But let’s be clear, this is not remotely close to a Fenix killer. Instead, it’s much more attuned to be hurting sales of a COROS Vertix, or perhaps in some scenarios, a Garmin Instinct. But as you’ll see, price isn’t everything. Neither is feature-check-boxing. The navigation section will make that really clear.

Still, this is not AmazFit’s first BBQ. And each time they release a watch they get closer and closer to being a premium competitor, but at a budget price. In effect, AmazFit is kinda like COROS, before COROS grew up and started spending time on new feature development, instead of just product comparison checkbox development.

With that, let’s get into it.

Oh and lastly, I purchased this unit myself. AmazFit did attempt to send me a media loaner unit, but alas it got caught in Spanish customs jail long enough that we both gave up on it, and I just went to Amazon to buy one myself. I end up re-purchasing most watches for long-term comparisons anyway, so…shrug. As always, I don’t accept advertising from any company I review – so, if you found this review useful, consider becoming a DCR Supporter, which gets you an ad-free site, plus the behind-the-scenes video series between both myself (and my wife) on everything that happens in the DCR Sports Tech Cave/universe.

The Core Specs:

Listing watch specs these days is kinda like throwing spaghetti at a wall. There’s a lot of different directions you can go in. But in some ways, that’s apt for the AmazFit T-Rex 3, since it covers so much ground. To be clear, this list is not inclusive of every feature, but rather, some of the big-ticket items that give you a rough outline of what this watch is.

– 48mm watch (48.5mm) weighing 68.3g
– Body is plastic with stainless steel top bezel piece
– 1.5” AMOLED touchscreen display (480x480px) with Gorilla Glass
– Optical HR sensor (with SpO2, HRV, skin temp monitoring)
– 24×7 activity tracking and sleep tracking
– Has 177 sport modes (most of which is just categorization, not unique sports features)
– Freediving to 45m (with EN13319 certification)
– Structured workout support,virtual pacer, track running mode
– Supports external sensors including heart rate straps, cycling power meters, cadence/speed sensors, running power, CORE body temp sensors
– Uploads to Strava, Komoot, Apple Health, Google Fit
– Downloadable global free maps
– Basic navigation following imported routes
– Microphone for voice commands (albeit, no speaker, just a beeper and vibration alerts)
– Includes WiFi, Bluetooth connectivity
– Multiband/Dual Frequency GNSS
– Smartwatch battery claim is 13 days (I find it closer to 7-9 days)
– GPS battery claims: Range from 42 hours to 180 hours, depending on mode
– Price is $279/€299
– Additional Premium Zepp app features for $69/year (e.g., more reporting/analysis, not used in this review)

As you can see, it’s an impressive list on paper. And to be clear, at a high level, almost all of these features have worked fine for me. What you’ll see though is that as good as AmazFit is at adding features, many of them are skin-deep at best. For some use cases, that may not matter. For example, it’ll work just fine as a running watch to track your runs. But want to push in structured workouts from another platform (like TrainingPeaks)? Nope, can’t do that. Likewise, basic navigation works well, but want to easily create routes within the AmazFit app? Nope, can’t do that.

Which isn’t to say that AmazFit won’t get there. They will, but it’ll just take time (years). Still, it’s incredible progress thus far – so, let’s dive into how well it actually works.

The Basics:

In this section I’ll cover most of the non-sports features. Things like basic usability (buttons/touchscreen), 24×7 activity tracking (e.g.,  sleep/steps/etc…), as well as their voice assistant and overall app features (their smartphone app is called Zepp). After this, we’ll get into the sports bit, the mapping/navigation bits, followed by accuracy.

Starting with the hardware basics, the unit has four physical buttons on the sides, and a touchscreen atop it. The four buttons work well in terms of daily interaction, both sport and non-sport usage. Likewise, the touchscreen is generally pretty good for both wet and dry integrations. Said differently, at no point over the last while has it been a problem for me.

The screen is a 1.5″ AMOLED touchscreen, that can be configured as gesture-based or always-on. In my case, I’ve been using it in an always-on configuration the entire time. The exception being at night it goes into sleep mode, which requires a tap to wake the screen (to ensure it doesn’t blind you in the middle of the night).

Now that said, one of the themes you’ll see with the T-Rex 3 (or AmazFit in general) is it’s nuances that matter. And the best example of that is actually how the screen handles gesture-based movements, such as when a text message comes in. For most watches, the watch won’t show the text message until you twist your wrist towards you. In many ways, how well they detect this tiny movement is sorta the hallmark of how good a company is on their smartwatch journey.

Unfortunately, as silly as it may be, it’s actually one of the things that frustrates me the most about the T-Rex 3. The gesture recognition is terrible, requiring significant hideously huge over-dramatic movements to get it to show my text messages. Else, it just stays on the watch face, but shows that a text message is pending. Now, is this the end of the world? Hardly. In fact, most of the issues with the T-Rex 3 are minor on their own. Rather, it’s the culmination of many little things that sets it back from the pack.

In any event, let’s look at the various data widgets as you scroll down. These are technically called ‘Shortcut Cards’, and you can customize them (including ordering) in the Zepp app (yes, that’s what AmazFit calls their app, because Zepp is actually the parent company name of AmazFit). By default, the top one is ‘Zepp Flow’, which is their voice assistant bit. After that, there’s music, ‘Recommendations’ (which never changes), and a slate of more usual ones like weather, last workout, workout status (aka Training Status), and more:

One thing you’ll notice is that while it renders and displays these instantly, the data is actually ‘old’ for the first second or two for each widget, before it then pulls in fresh (today’s/current) data. It’s bizarre, but again, part of the little quirky nature of the watch.

Zepp has a lot of features that are sorta there. For example, it has contactless payments, but only via Curve – not other cards (and within Curve, it doesn’t include the US). Curve is basically a prepaid Mastercard that you can create an account with, and then load onto the watch. It’s more popular in the UK than other places, and does at least fill the payment gap here. For most of us, paying with your watch is less about going to Best Buy and buying a TV with your watch, and more about stopping at a cafe after a long run to grab a drink/snack. So in that context, having a pre-loaded account is good enough for most. Still, setting up a Curve account does require sending some form of government ID in, as well as other personal details. Additionally, while the company advertises a standalone Mastercard connection, it doesn’t actually allow me to do that anymore, and I can’t find any evidence you can do that without a Curve account anymore (and the app only shows Curve and Account2 as supported).

Next, we get to sleep tracking, which unfortunately, didn’t work at all for me for the first week or two. To be clear, I’m not talking about having inaccurate data – rather, it literally wouldn’t track a single minute of sleep. Turns out, this isn’t a new problem for AmazFit, or the T-Rex series. A simple Google search reveals this is somewhat common – and despite numerous people having reported this and sent logs to AmazFit, there’s been no resolution for years.

Thus, every day for the first few weeks, this is what I’d see in my sleep tracking details:

Just nothing. It’s like the Simon and Garfunkel song, ‘The Sound of Silence’, except, no sound. Just…nothing.

At least, that’s what I thought was happening. However, upon closer inspection it was even weirder. In reality, it *was* tracking sleep each night on the watch, and if I looked early/quick enough in the morning I’d see those details on the watch. But, the second it synced that data to the Zepp app on my phone, it’d erase my sleep data entirely (on both watch and phone). In fact, it’d also erase all step/activity data too, just for funsies. Recorded workout sessions did however remain.

After some back and forth with AmazFit, the eventual solution was both resetting my watch *and* deleting the AmazFit (Zepp) app off my phone entirely, before starting over again. Since then, it’s been fine.

The good news is once I got said sleep data, it’s been quite accurate in terms of the time I fell asleep and woke up. It captures that well, such as below:

In fact, just yesterday one of my daughters wasn’t feeling well, so after getting the other daughters off to school, I went back and laid down with her for a few hours.Likewise, it also supports nap tracking – which has also worked well for me. Note that it does display sleep phases/stages, though as is always the case, I don’t attempt to rate the accuracy of that. That’s because the comparative technology to do so simply isn’t all that accurate by itself (only in the mid-80% accurate range in a best case scenario, but usually 60-70% accurate). We’d never judge heart rate accuracy on something only 80% accurate, so I’m not sure why some reviewers try to do the same for sleep phases. I’m personally far more concerned with whether it got my falling asleep/wake-up times correct.

That said, the sleep scores it gives me are very…consistent. Far too consistent. No matter what I do in terms of sleep, it’s basically the same every day:

Which then gets us to the ‘Readiness’ score. This score is aimed at taking your sleep metrics, recovery metrics (post-workout), activity data, and more, and giving you a score for how ‘ready’ you are. It’s roughly designed to mimic Fitbit’s Readiness Score and Garmin’s Training Readiness score, except unlike those, without actually being useful.

Here’s some of the metrics it pulls from the app for a single day’s Readiness Score:

But more importantly, here’s how that score has changed week after week, month after month.

As a quick game of ‘spoiler’, it hasn’t changed. No matter what I do workout-wise (including back to back to back days of 3-4hr long mountain rides), to just 3-4hrs of sleep, it simply stays at roughly 75-90…every…single…day. So much so that even when the watch was zapping my sleep, it’d *STILL* generate a readiness score in the same range. Said differently: It’s entirely useless to assess readiness.

The funny thing is that by itself, the AmazFit tends to get all the individual metrics correct. Rather, it’s the sum of the parts that goes off the rails. For example, in addition to the sleep metric, there’s HRV (Heart Rate Variability) tracking, and looking at that data, it’s been within the realm of other devices I have (all three of the below use all-night averaging).

Just picking a random night in the past week:

AmazFit T-Rex 3: 51ms
Oura Ring Gen4: 49ms
Whoop 4: 48ms

Each device measures at slightly different intervals, with the T-Rex 3 seeming to have a much lower interval/frequency, which may be why it’s slightly offset from the others.

Lastly, AmazFit has a few other areas like their voice assistant, Zepp Flow, which has a marble-looking icon and then you can audibly ask it things:

Except, I found it doesn’t quite seem to translate things super well. For example, above, it clearly hears me ask about the weather *tomorrow*, shows me it understands the question, and then instead gives me the weather for *today*. Note, it gives the answers visually on the screen, rather than audibly via speaker. It seems to do well when you ask it something that it can explicitly accomplish on the watch. But if you ask just about anything that’s a real question (e.g. “Should I run today?”), it’ll start offering you random things instead.

Still, as I said early on – the battery life continues to be impressive for me in smartwatch mode. I’m pretty consistently getting about a week’s worth of battery life, and this despite having many (GPS) training days each week at 2-4 hours each, on average probably close to 2hrs/day of workout time. And all this with the always-on display for both workout and daily smartwatch use, as well as using optical HR for workouts (and connected to a cycling power meter for cycling workouts).

For charging, it clips onto a magnetic base clip, that you in turn attach via USB-C cable:

While battery life lasts forever, that’s also true for charging – it too takes forever. AmazFit quotes 2.5 hours to fully charge, which does seem in the correct ballpark. It’s always long enough that I just go and do other things for a few hours and come back and it’s nearly done.

Charging time aside though, all other things related to charging and battery life are great – so, kudos on that.

Sports Features:

The AmazFit T-Rex 3 has an absolute boatload of sports profiles, as of this writing, some 177 to be precise. AmazFit has them all listed here, though realistically it’ll have every sport profile you can imagine – even bocce ball. AmazFit’s path to so many profiles essentially comes from an aggressive categorization game. Meaning, instead of just having one sport profile for ‘dance’, they break it out into: “Square dance, Ballroom dance, Belly dance, Ballet, Street dance, Zumba, Latin dance, Jazz dance, Hip-hop dance, Pole dance, Breaking, Folk dance, Dance, Modern dance, Disco, Tap dance”. None of these capture data differently from each other, it’s simply so you can track how much time you spend in each profile long-term.

Of course, there’s absolutely nothing wrong with that from a categorization standpoint. In fact, we’ve actually seen a general industry trend of adding more categorization-based sport profiles in recent years, compared to companies historically only adding sport profiles when there was unique per-sport data (e.g., gathering wave data for surfing, or jumps for mountain biking). However, consumers have made it clear: They want categorization of their activities, even without unique per-sport data.

In any event, circling back to starting a sport, you’ll tap the upper right button to get into the sport menu:

Here you can scroll through and select from your most commonly used sports, or dive into all all of the other sport categories:

In case you’re wondering, ‘Extreme Sports’ includes ‘Wingsuit flying’ (I agree with that descriptor), while leisure sports includes ‘Hula Hooping’ (and again, I agree with that descriptor too). Meanwhile, ‘Board Games’ includes Chess, Checkers, and Go…but sadly, not Monopoly or Jenga.

In any event, once you’ve picked your sport of suffering, you can tap it to find GPS (if applicable), or configure settings. These include bits like workout alerts/goals/auto lap/auto pause/virtual pacer, as well as structured training, including intervals. For intervals, you can configure distance or time-based repeats, the quantity of repeats and recovery, and whether a warm-up or cool-down is added.

Meanwhile, in the app itself, you can create structured workout ‘templates’ for each sport, that iterate through on various targets. There continue to be some quirks. For example, in structured workouts, instead of using the (proper) term “Recovery”, they call it “Break”. I know it sounds like nitpicking, but there are endless examples of this throughout the AmazFit app/platform. Note for cycling workouts, you can’t specify cycling power as a target, only heart rate or speed.

Back to our run though, once we’re ready, we’ve got GPS lock and can press the ‘Go’ button to start.

At this point, you’ll see your data pages/fields as you’ve configured them via the app.

Speaking of which, you can customize these to upwards of 6 data fields per page, which is done from the watch itself (within a sport profile mode), and you can add multiple customizable pages.

Likewise, you can also connect to various Bluetooth sensor types, including heart rate sensors, running power meters (e.g. Stryd), cycling power meters, cycling speed sensors, and cycling cadence sensors. To pair sensors, you’ll swipe down from the top, then tap the Bluetooth icon on the second page, and then choose ‘Workout Accessories’. From there, you can start your pairing.

That said, it’s been hit or miss for me. The JetBlack Victory Smart Trainer paired without problems, yet the Quarq RED power meter (2024) pairs and connects sometimes, and fails other times. Frankly, I’d have expected the opposite – since Quarq Bluetooth power meter pairing has been around for roughly a decade now. And even once paired with the JetBlack Victory and showing power on the watch and in the app, it fails to send that power data to Strava (but does export it at least to the .FIT file, via the exporter in the app). Again, it’s yet another example of a half-finished feature.

In terms of running/riding with it, it worked perfectly fine for me in all my workouts from a data/usablity standpoint. Meaning, I had no problems using it for pacing or distance/etc… I think that’s one of the things that many overlook when looking at running/etc watches. By and large, all of these watches do the whole “how fast/how far” thing quite well. In fact, I’ll give extra credit that AmazFit even has a ‘Resume Later’ option (handy for multi-day treks or long breaks).

Once your workout is complete, you’ll see a summary on the watch itself:

And likewise, on the app:

All of which then syncs off to apps like Strava and others. And, you can also export out .FIT files directly from the app (kudos on that, wish more companies did that). However, as always, there are quirks. For example, the exports to Strava don’t contain your cycling power data (if you had a power meter). Sigh…

Likewise, I’ve also had a few workouts, seemingly in the day or two following some water activities, where it was firing blanks for altitude-related data, such as elevation (this casual hike with the kids involved plenty of ups and downs, yet showed zero on the watch):

Though, on the app, it showed up properly:

Now in terms of training load and recovery stats, AmazFit will track your training load, and actually does a pretty good job of it at a high level. Though, the numbers I get from AmazFit tend to be double that of Garmin, but, in this specific area, the exact number isn’t important as long as it’s consistent (which, it is). I also *GREATLY* appreciate that AmazFit correctly shows your 7-day trending load, and doesn’t reset it every Monday morning (like COROS and a few others do, entirely missing the point of training load):

However, in terms of VO2Max values, they’ve been substantially below my recent tested VO2Max, and all other devices. Further, the unit does not calculate any VO2Max for any sports except running.

In terms of ‘Recovery’, there are two pieces. First, it’ll list a recovery time (presumably until the next hard workout):

And then within the Readiness bits, there’s also the ‘Physical Recovery Score’, which…umm…never really changes much.

Finally, a quick note about free diving. In this scenario, the unit is limited to 45m of depth gauge details – beyond that it won’t display accurate depth (until you get back within the 45m range). The unit doesn’t have a Scuba profile, but instead, has ‘Outdoor freediving’, ‘Indoor free diving’, and ‘Spearfishing’. Further, it also has snorkeling.

When you open a free diving profile for the first time, it’ll warn you of various risks of both the limits of the device, and free diving risks generally.

Within the settings, you can change the water type, though more notably, you can customize alerts for diving depth, duration, as well as surface interval alerts.

After that, you’re presented with the start screen, where you can press ‘Go’. Though technically speaking, it won’t actually start the counter until you submerge (GPS is used though to mark locations on the map):

In my case, I’m a scuba diver, but not a free diver (goals for the spring…), so this was more just snorkeling and casual diving down to about 6 or so meters (~18-20ft) to show how the depth gauge works. I ran out of water depth in this bay to go any deeper. Sad panda.

On the unit (by default) you’ll see your current/max depth, ascent information, water temperature, and heart rate. Plus the compass. But you can customize these as you see fit.

But yet another example of a little quirk though is that I got a 10% battery alert notification pop-up mid-dive. I couldn’t dismiss it with the buttons (and obviously, not the touchscreen).

It eventually disappeared when I got to the surface, but this is the sort of thing that would absolutely constitute a huge safety violation on any other dive computer (specifically, the inability to dismiss it and see your depth, not the actual alert itself). Again, it might sound minor, but it’s seemingly minor things that are really important to get right.

Nonetheless, afterward in the app you’ll see a recap of your dive profile, including each dive listed/shown, as well as the depths/times:

Setting aside the battery bug, all of this is super cool to have in a low-priced device. While the 45m max limit is kinda low for more advanced free divers, it’s totally fine for snorkeling and other shallow fishy activities. Most other watches that have a depth gauge are limited to either 7-8m (Suunto Race for example), or 40m (Apple Watch Ultra 2, Garmin Fenix 8, etc…). And the Suunto Ocean at 60m. However, all of those are $800+.

Mapping & Navigation:

The AmazFit T-Rex 3 includes the ability to download maps to the watch from the app, including base maps, Ski Maps, and Contour Maps. After which, we’ll get into the routing capability, but, I’d read this section carefully, because as is often the case with AmazFit, the details matter.

To start, you’ll crack open the app and go to Device > Map, and then zoom out to the area you want to cover, such as below:

From there, you’ll go back to your watch and select Settings > Map > Map Resources, to actually see the status of said download. It’s a little bit cumbersome that it doesn’t just start downloading immediately. It’s here you’ll need to configure WiFi if you haven’t already. WiFi is required for map downloads (like most watches, though COROS does allow map downloads via Bluetooth).

From there it’ll start the download of the map. It took about 2 minutes to download the whole island of Mallorca, an area I defined as roughly 100km x 175km. You can download multiple map regions, so in my case I also downloaded one for the Netherlands and Belgium as well, which took a little bit longer – about 10 minutes. But that’s pretty darn reasonable, given how big it was.

At this point, you’re ready to start navigating a course or route, which requires first getting a route onto the device. That part is a bit messy. Unlike all their competitors, AmazFit doesn’t have route connectivity for Strava Routes (though they did recently add Komoot Routes, more on that in a second). Instead, you’ll have to manually export out the GPX/TCX/KML file from those platforms, save it to your phone, and then import it back into the AmazFit app, after which you’ll push it to the watch.

For example, I created a trail run in Strava, then downloaded and saved the .GPX file to my phone. On my phone, I selected it via the Files app (an iPhone), where I told it to use the Zepp app to open it, which then pulled the route into the Zepp app (note that if you use Strava’s mobile app, there isn’t really any easy way to export a file out, instead, you need to use their website from your phone).

Once in your Routes library, you can choose to send it to an AmazFit device, in this case the T-Rex 3:

 

After which, you’re able to head outside and start routing on it. To do so, you’ll open a sport profile (e.g., hiking/running/etc…) and then select navigation. From here, you can select the route.

You can see various details about the route, including elevation and climbs:

Once you’ve started the route, you can navigate atop it. You’ll see a line (red in my case, though you can customize it), and then my current position on that line. You’ll also see the distance remaining on the course listed (5.87km in my case).

You can switch the orientation in the map, though oddly by default it’s North Up (versus the direction of travel up like most watches).

In any case, as you approach a turn, you’ll get notice about it:

If you deviate off the course by 50m or more, you’ll get a quirkily worded warning about that as well. Though interestingly, you can customize the deviation distance (e.g., setting it for 20m/50m/100m/off).

Still, there are weird things in mapping land. Firstly, is that it doesn’t show water as blue…or anything near blue. I live on an island surrounded by the sea. Yet, the map in either map style, shows vast chunks of very firm rock ground as nebulous.

Just for context on the above, sure, the black section to the right of my position is water. But everything north of me is very much hard ground (3 red arrows pointed at hard ground that on the AmazFit map is water, and two red arrows pointing at the sea).

Again, I very much appreciate that AmazFit makes downloading maps easy, but these aren’t good maps.

Now, in addition, AmazFit recently added Komoot route support, though, it’s pretty funky. It seems like a feature that was built by a single person that wasn’t allowed to integrate with the rest of the app. It’s oddly silo’d away from everything. Normally, you’d see your routes in your route library – but that’s not how the Komoot ones work. To get to these routes, each time, you need to go to:

Zepp App: Profile > 3rd-Party Account Linking > Komoot > Import Routes > [Manually refresh each time] > Tap route name > Save

Then, once that’s done, you need to send it to your watch, so, there’s more steps:

Zepp App: Workout Tab > Scroll to bottom > My Route > Tap route name > Send to device

What’s funny is how near identical this process is to the COROS route sending process. The UI looks identical, the waiting/sending prompts are identical, everything is the same. So much so that I can’t decide if AmazFit has licensed it from COROS, or just blatantly copied it. Sadly, I wish AmazFit copied other features from COROS instead of this one, as this continues to be the singular feature that frustrates me the most on the COROS platform.

Nonetheless, once it’s synced, then you’re good to go just as with before and the manual routes.

As much as some YouTubers want to proclaim this to be a ”Fenix Killer” or ”Garmin Killer”, it’s the navigation and routes pieces that show just how insanely far that is from reality. Sure, it’s got maps at a bargain price, but those maps suck. If I don’t know I’m walking towards an ocean/lake and think it’s land, how useful is that really, when it counts?

Likewise, the route import process is incredibly clumsy – without any ability to create a route in the app itself. Thus, you’ve likely gotta pay for another platform to create your route. Again, AmazFit is going in the right direction, but the product as it is today isn’t really ready to compete with most other units on the market.

GPS & Heart Rate Accuracy:

With well over 2 months of near-daily workouts on the T-Rex 3, I’ve got a pretty good grasp of where it works well, and where it falls apart from an accuracy standpoint. Thus, rather than drop some 60 workouts in this section, I’m highlighting the ones that both most representative of the performance, as well as some ‘interesting’ ones from a route/complexity/etc standpoint.

In this section I’ll cover heart rate accuracy, GPS accuracy (configured in the best possible accuracy mode), as well as elevation/altitude accuracy. I’ll be doing so against other units concurrently used during each ride, including trusted heart rate sensors and watches/bike computers. I’ll mostly skew towards more recent workouts, though I saw no real change throughout this time period.

With that, we’re gonna jump straight into it with a 90-minute interval run from earlier this week. Sure, I could show you easy stuff first, but there’s no reason to – it aces all that. And in fact, it also nearly aces this interval run as well. Here it is compared to an Apple Watch Ultra 2 on the other wrist, the COROS HR band, and a Garmin chest strap:

You can see only a handful of very tiny errors, first at the beginning for a few seconds here or there, and then at the end of the very last interval, when I held up a camera to take a short video, that tripped up the optical HR sensor (somewhat rare, but also not a huge issue).

From a GPS accuracy standpoint, this was loop after loop, though the first loop did go through the downtown portion that included countless high-rise hotels, and it had no issues being in the shadow/overhangs of that:

Here’s a zoomed-in look:

Now, I’ve done trail runs as well – though frankly, those too have been identical to this. Boringly perfect. In fact, almost all of my runs have been pretty much boringly perfect regardless of terrain/environment, or interval structure.

So instead, let’s change sports, and switch over to cycling. First, we’ll start with an indoor workout – this one a 1hr 45min trainer ride:

At a high level, it too looks very very close. Though again, in the first few minutes during the warm-up period, there are some moments of struggle, especially when I shift into some short bursty intervals. Here the Apple Watch Ultra 2 tracks these changes much faster.

Nonetheless, the remainder of the workout was just fine, virtually identical to the other heart rate sensors.

So let’s head outside, to increase complexity. This ride was the famed Sa Calobra route in Mallorca. It’s a series of climbs and descents. That’s notable, because you’ll see which sections it really struggles in (though, seemingly, all of them). I’ve put arrows on each section, indicating whether it was up or down, and to a half-hearted degree, how steep it was (which roughly corresponds with speed, which can influence road vibrations).

As you can see, it did OK during the first climb for the first 45-50 minutes. However, after that part, it struggled very heavily. I’d have expected struggling on the descents (common for optical HR sensors while cycling. But I’d have fully expected the main climb (starting at ~2hrs in) to be super easy for the unit. After all, it was a steady climb on smooth pavement for 45 minutes. But alas, it was a hot mess.

On the bright side, shifting to the elevation realm, things are pretty solid there. The three units were generally within at 15m the entire time (the slight delay you see on the Edge 540 at the end is simply because it got paused for a minute or so, hence the offset):

In terms of GPS, again, no issues here, despite twisty-turny roads in the mountains, under tunnels and whatever other crazy road-in-cliffside creations the country of Spain has decided to create. At a high level, it’s obviously hard to see in the data:

But once you zoom in, things are solid, despite some of this being descents at 50-60KPH:

And again, here too:

And again, no matter which rides I look at: Mountain, trail, road, city, etc… all of them are virtually identical. Zero problems, very solid.

Lastly, we’ll take a quick look at an openwater swim. This is one of a few swims, but, is the most recent one. Albeit not the best one, the previous one nearly two months ago was slightly better, though, not massively so. Whereas this is definitely on the lower end of GPS accuracy for an openwater swim. Here it is, alongside the swim buoy reference track (a GPS unit attached to a swim buoy above the water, using a clean GPS track):

If you zoom in, you can see the T-Rex 3 is definitely pretty wobbly:

This isn’t a deal-breaker obviously, but it isn’t in line with most other products in the market today from a variety of companies. Heck, even COROS managed to finally fix their openwater swim issues in recent units – thus putting most companies in the same ballpark.

Still, setting openwater swims aside, I’m pretty darn happy with accuracy for GPS and elevation, and running heart rate + indoor cycling. Cycling outdoor heart rate obviously leaves much to be desired though.

(Note: All of the charts in these accuracy sections were created using the DCR Analyzer tool. It allows you to compare power meters/trainers, heart rate, cadence, speed/pace, GPS tracks, and plenty more. You can use it as well for your own gadget comparisons, more details here.)

Wrap-Up:

Each year AmazFit gets closer and closer to being a viable brand in the endurance sports watch category. And, depending on your criteria, it may already be one. The company’s strategy to date has largely been “Yes to everything”, at least at the surface level. As a result, when comparing this device to others from a feature standpoint, it appears to do well. That rewards both lazy reviewers, and the company alike. And certainly, there are some features it does well – and even better than, existing companies in the space. And obviously, the price is incredible, be it on sale or otherwise.

The problem though is ironically not the hard stuff that most newer watch companies struggle with. The GPS and heart rate accuracy have actually been solid for me. Likewise, the battery life is also fantastic. And while we all have our style preferences, in terms of durability, it seems solid too. And heck, nobody else in this market has a depth gauge in their watch anywhere near this price point (or even 2x this price point).

Instead, most of the software features seem only surface-level finished. For example, mapping is usable until water is involved (lake/ocean/river/etc), and then you realize the maps don’t differentiate between water and not-water (crazy as that might sound). Likewise, the recent Komoot Routes integration is clearly half-baked at best, buried deep in unrelated menus and falling far short of all their competitors implementations. Same goes for contactless payments, which in the real world only works with a single payment processor that most people don’t have or want to sign-up for. And all this sets aside the diving safety issue I ran into, or the endless nagging to sign-up for their premium platform.

But again, as I said earlier, much of this reminds me of COROS years ago. At the beginning, they mostly just copied Garmin (fonts and icons included), and undercut deeply on price. But over time, they got better and better at doing their own dance, and actually innovating on more than just price. In the last year or two, COROS has started to understand that finishing software features is more important than quantity. As a result, they’re putting out products (like the COROS Pace 3 and COROS Pace Pro) that are not just paper competitors to Garmin/Suunto/Polar, but very legit competitors. COROS has slowed down the endless churn of often half-baked software features, to deliver fewer but fully cooked features.

If Zepp/AmazFit can make that transition, they could become a very legit competitor in the endurance space. That requires them not only focus on finishing features, but also updating existing watches (another pain point of the company, which typically just releases a new model instead each year, rarely offering meaningful updates for previous owners). Because again, it’s clear they are innovating on price, or even the quantity of features included in a watch (such as voice commands or free diving at this price point).

And for everyone’s sake – I hope they can make that transition, as it’d be fantastic to have more competitors in this space that athletes can look to. That’s the best thing for all of us.

With that – thanks for reading!