Amazfit T-Rex Review - Outdoor Smartwatch for athletes

Test: Amazfit T-Rex

Many smartwatches, especially in the sports sector, are designed to withstand at least water. The Amazfit T-Rex goes one step further and appears as a particularly robust smartwatch.

According to the MIL-STD-810 standard, which defines test conditions for military equipment, the T-Rex has passed a total of 12 endurance tests. According to Huami, the smartwatch is temperature-resistant from -40 ° C to 70 ° C, moisture-resistant for 240 hours and offers 96 hours of protection against corrosion.

Design, workmanship and delivery

Watch case in outdoor design

Huami is unmistakably based on an eye-catching “rugged design” with which the Casio G-Shock watch series achieved cult status that continues to this day. The massive polymer watch case embodies the special durability of the Amazfit T-Rex.

The total thickness of the circular case is 13.5 mm, with a diameter of 47.7 mm. In contrast to the robust look, the smartwatch is comparatively light with a weight of 58g (including bracelet). Even during strenuous activities, whether at work or in your free time, the T-Rex remains comfortable to wear.

The bezel sits like a protective hood on the 1.3 inch touch display. Four metal screws, which connect the bezel and the rest of the watch case, add to the extravagant look.

Four function keys

In addition to the touch display, the smartwatch can be operated using a total of four function keys positioned on the side. The functions are "Up" and "Down" scrolling, "Select" and "Back". The function of the respective key can be seen from the labeled bezel.

The additional operating option is definitely an advantage. Especially in outdoor use, where you may be wearing gloves and have no access to the touch display, the smartwatch can still be operated.

5 ATM water protection

The Amazfit T-Rex can withstand a pressure of 5 ATM. This corresponds to the pressure of a water column of 50 meters. What sounds like a lot at first, according to the general classification, is only sufficient for showering and washing hands. You can expect more from an outdoor smartwatch!

 According to Huami, swimming is also possible, after all, there are also two swimming programs, but caution is advised here. Only from 10 ATM are watches suitable for swimming without hesitation. Diving and snorkeling, but also salt water and steam baths, should definitely be avoided with the T-Rex!

Robust silicone wristband

Huami has opted for a pleasantly soft and at the same time robust silicone bracelet. The watch strap is adjustable in size in 19 steps, measures 19.5 cm in length and is 26 mm wide. A pin buckle keeps the smartwatch securely on the wrist.

A change of the watch strap is possible. However, there is no quick-change system, which is why you have to use a screwdriver. The bracelet is held in place by strap screws. The bridge width is identical to that of various Casio G-SHOCK models. In the test, we were able to exchange the bracelet for a Casio G-STEEL GST-W310 bracelet.

Processing quality and scope of delivery

The build quality is good. The scope of delivery does not differ from other Amazfit smartwatches and includes the charger and a multilingual quick guide in addition to the smartwatch. The watch is available in the colors "olive green", "metal gray", "stone black", "camouflage color" and "khaki".

Display

Round AMOLED display

The round display with 1.3 inch diagonal and high 360 x 360 pixel resolution is of the type AMOLED. The main features of this type of display are intense, downright bright colors and a strong contrast with deep black levels.

At the same time, AMOLED displays are considered economical in energy consumption. The display type does not require a backlight, because each pixel is controlled individually via an active matrix. Pixels that are not required simply remain switched off and therefore do not consume any energy.

Display in everyday life

The AMOLED display of the Amazfit T-Rex is convincing in everyday life. The display is sharp and the maximum display brightness is sufficient to be able to read the display easily even in the sunshine. An automatic brightness adjustment is available and continuously adjusts the display brightness to the ambient light. The touchscreen reacts quickly and precisely to inputs.

The always-on function, which is thanks to the economical AMOLED panel, is practical. The display remains switched on and shows an energy-saving version of the dial.

Gorilla Glass 3 screen protector

The display is protected by hardened Gorilla Glass 3 from Corning. The display glass is considered to be particularly scratch-resistant and shatterproof. A special anti-fingerprint coating makes fingerprints more or less invisible and ensures a pleasant glide on the display glass.

Functions of the Amazfit T-Rex

In addition to a robust design, one expects a range of useful outdoor functions from an outdoor smartwatch. Unfortunately, the T-Rex is a bit weak in this regard. GPS + GLONASS and a compass are available, sensors such as a barometer, an altimeter or the ability to navigate with the smartwatch are missing.

Except for the design, the T-Rex does not differ from other Amazfit smartwatches. Here, too, the proprietary Amazfit OS is used, which is functionally linked to Huami's specifications.

Service

The user interface is not one of the most responsive, but it is clearly structured and easy to use. From the homescreen you can get to the quick settings with a swipe upwards. With a downward swipe you get an overview of the current number of steps, the distance covered, the calories burned and the heart rate. Vertical scrolling is also possible with the two physical buttons "Up" and "Down".

The user interface of the Amazfit T-Rex.

To access the app selection, you have to swipe horizontally to the right. A swipe to the left and you get to the notification overview. Unfortunately, there is no physical function key for horizontal scrolling, which is why the T-Rex cannot be fully operated using the side function keys.

Apps

As a user, there is no way to install new apps or to expand the range of functions at a later date. The following apps are already on the smartwatch: 

•  Status: Overview of the steps, the distance covered, the calories burned and the sitting behavior.
•  Heart rate: Measurement of the heart rate and graphic display of the measurements spread over the day.
•  Training: Choice of 13 sports programs.
•  Activities: Overview of the activities measured.
•  Weather: Current weather report (temperature, wind, humidity and UVI) with weather forecast.
•  Music: Control of the music playback of the smartphone.
•  Alarm (alarm clock), event reminder, timer, time control, phone search, compass, settings 

The order in which the apps are arranged can be individually set using the Amazfit app.

The Amazfit T-Rex apps.

sports programs

The Amazfit T-Rex is essentially a sports smartwatch. This is shown by the total of 13 sports programs, which are designed for different sports. The following sports programs are available: 

• Running outdoors
• Walk
• Cycling outdoors
• Pool swimming
• Open water swimming
• treadmill
• Spinning
• Cross trainer
• Training
• Climbing
• Cross-country
• skiing
• Outdoor trekking

 Triathlon has already been announced as another sports program and will be added soon via OTA update.

The sports programs of the Amazfit T-Rex.

Each sports program is specially tailored to the respective sport. For outdoor activities, for example, the GPS can be switched on, while swimming the length of the lane can be set in advance. In order to keep an eye on your own fitness, individual training goals can be set. Real-time diagrams provide information on athletic progress.

Some of the 13 sports programs have an automatic pause function. Huami implemented the feature well. Even if the activity is only interrupted for a short time, the sports program pauses.

GPS and outdoor

For an exact position determination the Amazfit T-Rex is able to communicate via GPS and GLONASS. It takes between 20 and 45 seconds for the location to be determined. The accuracy of the location determination is precise to a few meters and remains constant even when moving. A test run in the forest showed no serious deviations from a handheld GPS device.

Unfortunately, there is no export or import option for GPX or TCX files. It is not possible to navigate with the T-Rex! 

Activity tracking with the Amazfit T-Rex.

Heart Rate Monitor

There is a PPG bio-tracking sensor on the underside of the smartwatch that measures the heart rate. In the case of the T-Rex, green light is shone on the skin. The measuring process determines how much light is backscattered depending on the blood flow.

The procedure is considered to be reasonably accurate, although numerous factors can affect the measurement result. The T-Rex returned realistic values ​​in the test. Compared to a chest belt, the deviation was +/- 4 beats.

When the sports program is active, the watch continuously measures the heart rate. A 24 hour heart rate monitoring can also be set. The detection frequency (1, 5, 10 and 30 minutes) and a warning value can be set in the Amazfit app. The smartwatch does not offer an ECG function. Blood oxygen measurement (SpO2) is also not supported.

Sleep monitor, music control and others

If you want to wear the T-Rex in bed, you have access to a sleep monitor. This records the time to fall asleep and wake up and monitor the various phases of sleep. For this test, the T-Rex was allowed to stay on the wrist for one night. Otherwise, the watch is quite uncomfortable to wear while sleeping. The sleep monitor provides plausible recordings. In the event of a discrepancy, the time to fall asleep and wake up can be corrected using the Amazfit app.

The T-Rex's music app is not a music player, but makes it possible to control the music playback of the connected smartphone or tablet. The current song title is displayed, the volume can be adjusted, music playback can be paused and continued, and tracks can be switched back and forth.

Compass - music control - alarm clock - timer - time control

Notifications

Incoming notifications on the connected smartphone or tablet can be forwarded directly to the T-Rex. For example, if a WhatsApp message arrives on the smartphone, it can be conveniently read on the smartwatch. However, there is no answer.

This is what it looks like when a WhatsApp message arrives on the Amazfit T-Rex.

You will also be notified of incoming calls. These can be rejected or muted via the clock. It is not possible to make phone calls directly through the T-Rex. Which notifications are forwarded to the smartwatch can be set via the Amazfit app.

Amazfit app

The Amazfit T-Rex is an app-bound smartwatch. All Amazfit products are managed via the Amazfit app (Android and iOS). At the same time, the app is used to evaluate the tracked data. The collected fitness data are transferred to the app via Bluetooth and are available there in processed statistics.

If you don't like the app, you can synchronize all data with the Mi Fit app or send it to Google Fit or Strava.

Watch Faces

There are more than 30 watch faces to choose from in the Amazfit app, which can be transferred to the T-Rex at the push of a button. In addition, you can also install your own watchface creations on the smartwatch. There are numerous watchface communities on the net, on which finished watch faces are available for download.

Battery

Huami was able to accommodate a lush 390 mAh battery in the expansive housing of the T-Rex. The manufacturer himself specifies the running time as at least 20 days.

The value is quite realistic. In the test, we achieved a runtime of 16 days with just one battery charge. The smartwatch was used intensively every day. The following settings / functions were active:

• Automatic display brightness without always-on display
• 70 notifications received per day
• Evening synchronization of the data
• 3 hours of GPS
• 7 hours of indoor sports tracking
• 24 hour heart rate measurement (every 30 minutes)

The T-Rex is particularly economical in standby. The battery consumption was only 1-2% overnight. According to Huami, up to 66 days of standby are possible. The GPS, in turn, is the biggest power guzzler of this watch. One hour of GPS consumes approx. 6% battery. The always-on function increases battery consumption to approx. 16% per day.

The Amazfit T-Rex is charged via USB. The charging cable with 2-pin charging connector is held magnetically on the back of the watch. The battery is more than half charged after just 30 minutes. A full charge takes about 75 minutes.