Zepp Health has a number of good offerings for those after an outdoor smartwatch. In this article we look at several different options.
One of these is the Amazfit T-Rex Pro. A slightly upgraded version of the original, it was released last Spring. This is a watch designed for adventurers as it is built to withstand practically anything.
Next up is the Amazfit Ares from May 2020. Just like the T-Rex Pro, Ares is built to last. There’s no denying there are lots of similarities between them.
Essential reading: Top fitness trackers and health gadgets
The most recent additions to this list are GTR 3 and GTR 3 Pro. Both released a few weeks ago, they are part of one of Amazfit’s most popular lines.
If you’re in the market for an adventurers watch, you may be trying to decide between T-Rex Pro vs the GTR 3 range vs Ares. All of these present themselves as intriguing options. Read on to find out how exactly they differ.
Amazfit T-Rex Pro vs GTR 3 vs Ares: Design and hardware
Look and feel
Amazfit Ares and T-Rex look nothing alike. But they do share a lot of features.
The first has an octagonal shape and three physical buttons on the right. The watch lacks the Military Certification of T-Rex, but is still able to survive most situations.
The actual dimensions of the main unit are 46.5 x 55.5 x 14mm. Even though it’s fairly large, the device only weighs 48 grams thanks to its polycarbonate build. Additional specs include a 1.28 inch Gorilla Glass protected, reflective colour display with 176 x 176 pixel resolution.
T-Rex Pro comes in a more traditional round shape. A 1.3-inch, 360 x 360 resolution AMOLED display sits on top of a high-strength polymer 47.7 x 47.7 x 13.5 mm case. Along the sides are four physical buttons. The watch weights 58 grams, and that’s including the strap.
This is obviously a very rugged device, a competitor to the likes of the Garmin Fenix 6. In fact, it has US Military Standard 810g (MIL-STD-810G) Certification.
If you are wondering, the main differences between T-Rex and T-Rex Pro are the additions of a barometric altimeter, SpO2 sensor and stress tracking, better water-resistance and more satellite positioning options. So it is a nice, iterative upgrade.
Moving on quickly to Amazfit GTR 3. This one has almost the same dimensions as T-Rex Pro and Ares but it is quite a bit thinner and lighter. It is also more premium looking with its Aluminium Alloy body.
Another thing in Amazfit GTR 3’s favour is its large ultra-clear AMOLED display. This is definitely the highlight of this device and is one of the better quality displays we’ve seen so far on a smartwatch. GTR 3 comes with a 1.39 inch packing 454 x 454 pixel resolution. Its big brother had a 1.45 inch display with 480 x 480 pixel resolution.
Unlike the other two, GTR 3 and GTR 3 Pro have only two buttons. However, one of these is a rotating crown which offers a slick experience of scrolling through the menus simply by turning it.
Moving on to water-resistance and on this count all of these devices will suffice. They have an excellent 5 ATM water-resistance rating so you can safely take them swimming with you. This is even more impressive on the Amazfit T-Rex Pro which is good for depths down to 100 metres (10 ATM).
Under the hood
Under the hood the watches share Huami’s Biotracker PPG for monitoring heart rate. The difference being that Ares has the original version, T-Rex Pro BioTracker PPG 2.0 engine, and the GTRs PPG 3.0 engine. As you’ve probably guessed, accuracy of heart rate and other data should be better on the latest generation sensors.
There are a couple of other differences, too. Amazfit Ares is the only one on this list to lack the SpO2 sensor. GTR 3 Pro, on the other hand, is the only one on this list to pack a temperature sensor.
All these watches are equipped with built-in satellite connectivity. This is, of course, what you want from an outdoorsy watch. Amazfit Ares taps into GPS and Glonass, T-Rex Pro adds Galileo and Beidou to this list, and the GTRs add QZSS to all of this.
The awesome battery life is the thing we’ve come to associate with Huami watches. The good news is all of these devices will have you covered. In basic smartwatch mode they will keep ticking anywhere between 12 and 21 days. GTR 3 is the best performer of the lot. Switch on GPS and battery life will obviously come down drastically.
Here’s an overview of design and hardware differences between Amazfit Ares, T-Rex Pro and GTR 3s.
Amazfit T-Rex Pro
Amazfit GTR 3
Amazfit GTR 3 Pro
1.3 inch AMOLED
1.39 inch AMOLED
1.45 inch AMOLED
1.28 inch LCD
360 x 360 pixels
454 x 454 pixels
480 x 480 pixels
176 x 176 pixels
US Military Standard 810g (MIL-STD-810G) certification
47.7 x 47.7 x 13.5 mm
45.8 x 45.8 x 10.8 mm
46 x 46 x 10.7 mm
46.5 x 55.5 x 14mm
18 days in normal mode, 40 hours with GPS switched on.
21 days of battery life in normal mode and 35 days with limited functionality. GPS continuous usage time of 38 hours.
12 days of battery life in normal mode and 30 days with limited functionality. GPS continuous usage time of 35 hours.
14 days of battery life with 24-hour heart rate monitoring, 90 days in basic mode
BioTracker PPG 2.0 engine, 3-axis acceleration sensor, 3-axis geomagnetic sensor, barometric altimeter, SpO2, Ambient light sensor
BioTracker 3.0 engine, accelerometer, barometric-altimeter, geomagnetic sensor, gyroscope, optical heart rate, SpO2
BioTracker 3.0 engine, accelerometer, barometric-altimeter, geomagnetic sensor, gyroscope, optical heart rate, SpO2, temperature
BioTracker PPG biological tracking optical sensor, 3-axis acceleration sensor, barometer
GPS, Glonass, Galileo, Beidou
GPS, Glonass, Galileo, QZSS, Beidou
GPS, Glonass, Galileo, QZSS, Beidou
Yes (2.3GB for music storage – enough for up to 470 MP3 songs)
Yes (Chinese version)
Yes (Chinese version)
Bluetooth 5.0, WLAN 2.4 GHz
Amazfit T-Rex Pro vs GTR 3 vs Ares: Activity tracking and smart features
Fitness and health tracking
In terms of actual fitness and health functionality, there is really not that much to separate these devices. It comes down to small differences.
All of these watches use Huami’s proprietary operating system so the menus, navigation and smartphone app are the same. However, GTR 3 and GTR 3 Pro use the new Zepp OS, whereas the other watches use Amazfit OS. Having tried both, we can report that there really isn’t very much difference between the two. Both work well, although Zepp OS is a bit smoother and quicker. It also allows support for third party apps, but it will take time for the selection to build up.
Amazfit GTR 3
All the activity tracking basics are there on T-Rex Pro, GTR 3s and Ares – including heart rate and sleep monitoring. As mentioned above, Ares is the only one that lacks the SpO2 sensor for blood oxygen tracking. It also lacks around the clock stress tracking.
T-Rex Pro has SpO2 for on-demand readings, but the blood oxygen sensor has been upgraded to automatically capture measurements on the GTR and GTR 3 Pro. This makes the functionality much more useful.
The other difference is the temperature sensor on the GTR 3 Pro. It tracks your skin temperature which might be useful in these coronavirus pandemic times.
The differences also come when it comes to sports tracking.
Starting off with Ares, and that one has support for 70 sports modes and a few Firstbeat performance metrics to help you with improving your performance and recovery. There’s also Huami’s PAI health assessment built in. The dual satellite positioning system helps with accuracy when tracking outdoor exercise.
Amazfit T-Rex Pro allows users to choose between 100 different sports, including a host of popular outdoor activities. The Firstbeat performance metrics include Vo2Max, Training Load, Recovery Time Advisor and Training Effect (Aerobic). The satellite positioning is better than on Ares due to the addition of BeiDou and Galileo support.
Finally, the GTR 3s takes this a notch up. They are not much different for performance metrics, but the watches do bump up the number of sports modes to 150+. Eight of these are with auto-recognition. The latest BioTracker engine means heart rate tracking should be more accurate. The same is the case with satellite connectivity which benefits from the addition of QZSS support.
You also get the typical smart functionality on all of these such as notifications, music control, weather and more. The operating system is simple to use and works well. Amazfit GTR 3s, however, go a little further with NFC for on-the-go payments – but only if you live in China. They are also the only watches to support Amazon Alexa.
Worth mentioning is one extra that you get only on GTR 3 Pro – offline storage for music. The watch therefore has a built-in speaker and microphone. This also helps it to make and receive calls when connected with a smartphone. It is also the only one on this list to include WiFi connectivity. It needs it to allow you to transfer songs to the device (2.3GB for music storage – enough for up to 470 MP3 songs).
Amazfit T-Rex Pro vs GTR 3 vs Ares: The bottom line
Most of the differences between these watches come down to design, the functionality is fairly similar.
If you’re going for style, GTR 3 is the obvious choice. It comes with a stunning high-res AMOLED display, rotating crown and is lightweight and premium looking. It also benefits from the latest generation BioTracker engine, around the clock SpO2 measurements, better satellite connectivity and the new version of the operating system.
Take this a step further and go for the GTR 3 Pro. For the slight increase in price you’ll get offline storage for music and a temperature sensor.
Amazfit GTR 3 Pro
T-Rex Pro is the most rugged of all these watches. In fact it has a US Military Standard 810g (MIL-STD-810G) Certification so can survive most situations. It is probably the best choice for those purely looking for an outdoorsy watch.
Amazfit Ares has the least impressive design and display quality. But it offers 70 sport modes, some Firstbeat metrics and the most attractive price.
You can find all these watches on Amazon (check price).
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