Amazfit T-Rex 3 review: sports watch that’s amazing value for money

An impressive number of functions, so many cool ways to use it and at an outstanding price. Where to begin? Perhaps at the start. The new, eagerly awaited T-Rex 3 sports watch from Amazfit launched a few weeks ago. Galaxus has reported on this a few times. And manufacturer Amazfit was kind enough to supply me with a device to test out.

There are already lots of videos on YouTube from the usual reviewers. These often compare the T-Rex 3 with Garmin’s Fenix 8. It’s remarkable that two products in completely different price leagues are going head to head. At present, the T-Rex 3 is retailing for just under 300 francs on Galaxus, while the cheapest Fenix 8 will set you back slightly over 800 francs. That alone speaks volumes about the quality of the latest Amazfit design.

Amazfit T-Rex 3

The most important features at a glance:

• Colours: onyx, lava
• Dimensions: 48.5 × 48.5 × 13.75 mm
• Weight (without wristband): 68.3 g
• Case material: stainless steel bezel, polymer centre frame
• Buttons: 4
• Water resistance: 10 ATM
• Free diving certification: EN13319, ISO 6425, GB/T 18828 up to 45 m
• Display: AMOLED with max. 2,000 nits brightness
• Screen size: 1.5 inches
• Resolution: 480 × 480
• Touch screen: Gorilla glass

What’s included

The watch comes with a charging station, two adapters and a small tool. The latter is for replacing the wristband, while the adapters are designed to make any 22 mm strap compatible with the T-Rex 3. Amazfit has deliberately dispensed with a charging cable. What may seem strange at first makes perfect sense at second glance.

You probably already have several USB-C charging cables lying around at home. That’s the case for me, at least. According to the brand, this lets them save 3 g of metal and 4.5 g of plastic per cable. They also report that their packaging consists of 100% recyclable materials, and that it’s plastic-free and biodegradable.

Optics, design and display

The first thing that catches your eye with the T-Rex 3 is its octagonal housing. This may take a bit of getting used to for some people, but I like it. The case is 48.5 mm in diameter. It doesn’t come in any other sizes (yet). As a result, the watch is quite big and therefore not suitable for delicate wrists.

The T-Rex 3 is 13.75 mm thick and at 68.3 g, it’s averagely heavy. Its stainless steel bezel lends the watch a robust, high-quality look. Thanks to the 1.5-inch AMOLED display with up to 2,000 nits brightness and a resolution of 480 × 480 pixels, it’s very easy to read, especially in sunlight. The display also looks very bright and high contrast, which is typical for an AMOLED.

Amazfit also offers a night mode in this new model, which turns the display dark red.

Battery life

I’m spoiled when it comes to battery life. Very spoiled. Four years ago, after Garmin’s Fenix 6, I discovered Coros sports watches. Following on from the Vertix and Pace 2, the Vertix 2 is the battery-fuelled timepiece I usually have on my wrist. I’m talking about a battery life of up to 60 days. In comparison, the 27-day maximum offered by the T-Rex 3 seems rather modest. In practice, the battery lasts a good three weeks with the way I use the watch. So that’s not bad considering.

Let’s take a peek at the competition, in the form of the new Fenix 8. According to the manufacturer Garmin, it lasts up to 29 days on a single charge in smartwatch mode. Bearing in mind the big price difference between the two, this garners extra plus points for the T-Rex 3.

Sports and data accuracy

Amazfit supports 177 sports modes with the new T-Rex 3. From simple walking to free diving to HYROX race mode, everything’s included. I can’t think of anything else you’d need. The watch can be connected to peripheral training devices such as a heart rate belt, cycling power meter, bike computer and cadence sensor. And then you synchronise the data with third-party fitness apps including Strava, Adidas Running, Komoot, Relive, Google Fit and Apple Health.

I’ve been using the watch over the last few weeks for biking and strength training. And I went for a short jog again after a long break from it.

The T-Rex 3 collects countless pieces of data and displays them neatly in the Zepp app. Two questions always come up in these situations. For one, how accurate is the data from wearables and secondly, how do you interpret it correctly? About two years ago, I conducted an interesting interview with Dr Silvio Lorenzetti from the Swiss Federal Office of Sport. I’ve linked the conversation here:

In my opinion, the T-Rex 3’s data quality can’t be faulted and is comparable with the likes of my Edge 1040 Solar bike computer from Garmin.

Health features

Once again, the T-Rex 3 comes up trumps with its many functions. The two most important ones for me are the pulse monitor and heart rate variability, or HRV for short. Questions like those for sports data come up here, too. Measuring the pulse with an optical sensor on your wrist isn’t supposed to be as accurate as a chest strap. My experience with the new Amazfit watch seems to confirm this. Here’s how it analysed a gravel lap on the Strava platform. The biggest deviation is in heart zone 4 (red bar), where I was on the move for 12 minutes according to the Garmin, but only for a good 4 minutes according to Amazfit.

HRV is an important value when it comes to recovery. Which is why the watch measures the time between successive heartbeats during sleep. This value shows how my body reacts to physical stress and how it deals with recovery. After a few weeks of wearing it, the T-Rex 3 determines the corresponding values and establishes a lower, upper and average HRV.

Bear in mind that there’s no point comparing heart rate variability with other people. This number is in the millisecond range, and it varies from person to person. That being said, if the value is lower than the average, for instance, it may be a precursor to illness. Which is actually the case for me, as I’m currently struggling with a cold and my HRV is lower than usual. Thanks to the T-Rex 3, I already knew a few days ago that something was up (my nose).

Navigation and GPS

You can load maps onto the watch via the Zepp app. Select the desired area, radius and how you’d like the maps displayed. You can choose from basic maps, ski maps and those with contours and contour lines. You can then refer to these during a training session or hike.

I’ve used the maps at home and during my autumn holiday to Majorca. They display street names, points of interest or, in the case of topographical maps, contour lines and hiking trails. I’m yet to try out other free functions, such as Import route or Back to start.

Amazfit’s new watch uses a dual-band GPS that’s supported by six satellite systems. This is another example of the device providing all the features you could want. As far as GPS accuracy is concerned, the watch has nothing to shy away from. Both in open and rough terrain.

Smart features

To round things off, let’s take a brief look at the T-Rex 3’s many smart functions. And once again, there’s a wide range of applications. Having the option to play music on the watch or load your own songs onto it is certainly the most interesting feature for athletes. There’s a maximum of 26 GB storage space for maps, music, mini-programs, training records and watch faces. As the device doesn’t come with a built-in speaker, you’ll need Bluetooth headphones in order to listen to music. The T-Rex 3 only supports MP3 music files.

Another practical function is contactless payment via Zepp Pay. Thanks to integrated NFC technology, Zepp Pay lets you link up to eight bank cards at the same time. You can now make password-protected contactless payment straight from your watch. I can’t pass comment as I haven’t tried this or the music function.

There are lots of other smart features, such as the option to record voice notes or control the watch entirely with your own voice using Zepp Flow, which is based on OpenAI’s GPT-4o technology. But it’d go beyond the scope of this article to list all the available options.