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Xiaomi Redmi Watch 4 smartwatch review - Beautiful, but with software flaws

Oh, Xiaomi. The Redmi Watch 4 is beautiful, has a bright, large AMOLED display and a great battery life. It is inexpensive and at the same time has a satellite connection and a brightness sensor, but unfortunately, it annoys with many software bugs. Our review clarifies where the light and shadows lie.

Xiaomi is releasing the Redmi Watch 4, which retains the same basic design as its predecessor, the Redmi Watch 3.  It is slightly rounder, and the Watch 4 has a crown instead of a button. Unlike the top model, the Xiaomi Watch 2 Pro, the Redmi Watch 4 does not use WearOS, but Xiaomi's own HyperOS - which should ensure a long battery life.

Compared to its predecessor, the display has grown, and the smartwatch has even become slightly cheaper. The RRP is 100 euros. There is only one version of the Redmi Watch 4, but there are two colors to choose from: Obsidian Black and Silver Grey. As is usual with affordable smartwatches, there is no LTE version.

Xiaomi Redmi Watch 4
1.97 inch 15:13, 450 x 390 pixel 302 PPI, capacitive, AMOLED, glossy: yes
Brightness Sensor, Sensors: Heart rate sensor, accelerometer, gyroscope, electronic compass
Bluetooth 5.3, GPS
height x width x depth (in mm): 10.5 x 47.5 x 41.1 ( = 0.41 x 1.87 x 1.62 in)
470 mAh Lithium-Polymer, Battery runtime (according to manufacturer): 480 h
Additional features
Speakers: mono, Keyboard: on screen, charging cradle, Xiaomi HyperOS 2.1.53, 24 Months Warranty, GNSS: GPS, Galileo, Glonass, BeiDou, QZSS, 5 ATM, fanless, waterproof
48 g ( = 1.69 oz / 0.11 pounds), Power Supply: 10 g ( = 0.35 oz / 0.02 pounds)
99.99 Euro


Case and features - Redmi Watch with aluminum and stainless steel

The frame of the Redmi Watch 4 is made of an aluminum alloy. Our silver test device has a matt finish. A high-gloss line runs around the display, creating a visual highlight.

On the right-hand side of the smartwatch is a stainless steel crown that can be turned and pressed, which fits snugly. Haptic feedback when scrolling is generated by a vibration motor. Below the metal frame, in a black plastic panel, Xiaomi has also installed a speaker and a microphone on the right-hand side.

Without the strap, the Redmi Watch 4 weighs 31 grams; with the original strap, it weighs 48 grams. The band of the Watch 4 is made of TPU, has a width of 22 millimeters, and can be easily changed without tools. The manufacturer has provided two buttons on the underside for this purpose. However, the strap connection is proprietary, and only specific straps fit.

The strap is very long and is closed with a fixed pin; there is no classic clasp. It takes some getting used to when putting it on. On the test arm, the end of the strap regularly moves out of the strap loop and sticks out a little.

The build quality of the Watch 4 is very good. We did not get any scratches on the case during the test period. However, the gray strap has taken on a blue tint - probably from a pair of jeans. Xiaomi specifies the water resistance as 5ATM, but the Redmi Watch 4 does not have IP certification.

Setup and operation - Xiaomi relies on the Mi Fitness app

To set up the Redmi Watch 4, the Mi Fitness app is required, which is available for iOS and Android. When the Watch 4 is started for the first time, it prompts you to download the app. The app is used to scan a QR code on the smartwatch and the two devices are quickly connected.

The app then provides a short tutorial on the smartwatch operation, but nothing is displayed on the Watch 4. Overall, setup is completed quickly and the software can be explored on your own. It is noticeable that many measurements are deactivated ex-works, such as the continuous measurement of pulse, blood oxygen saturation, stress, and intensive sleep measurement.

If the measurements are activated, a warning appears that this change will affect the battery life. The Mi Fitness app is divided into four sections: Health, Training, Device, and Profile. Health is a dashboard that shows an overview of all health values in a map display. All completed training sessions are displayed under Training.

Device shows a list of the various paired devices. Xiaomi offers a store with a large selection of free watch faces. The settings of the paired smartwatch can also be changed, such as which apps are allowed to send notifications to the watch. The parameters for the health readings can also be adjusted. The display of the widgets on the smartwatch can also be changed via smartphone.

Other settings, such as the display brightness, the way the display is activated, the app layout, or automatic training detection, can only be changed on the smartwatch itself. There is no app store for the Redmi Watch 4. Local storage of music or contactless payment is also not supported.

As with the Xiaomi Watch 2 Pro, we have a few problems with the software of the Redmi Watch 4 in everyday use. From time to time, the smartwatch restarts for no apparent reason, which fortunately only takes a few seconds. More annoying is the fact that the Redmi Watch 4 sometimes displays the wrong time for hours, even if the paired smartphone - a Motorola Edge 30 Ultra in the test - is within range. Even repeated synchronization via the app does not help. The problem resolves itself after a while.

The Redmi Watch 4 is operated both via the 1.97-inch display and the rotating and pushable crown. Pressing the crown opens the app overview from the watch face. You can scroll through menus by turning the crown. From a menu, pressing the crown always takes you back one step. The button assignment cannot be changed, double pressing has no function.

A long press opens the start menu with the options switch off, restart, and reset. Pressing the crown three times can be linked in the app to sending an emergency text message to a specific number. However, this only works if a paired smartphone is nearby. In the test, entering an emergency number always resulted in an error message.

Swiping sideways from the watch face takes you through the various tiles. These are laid out as an endless carousel and can be scrolled through from both sides. Each tile contains various widgets; one tile shows information on the weather and sleep, for example, combined with a button to start a workout. Other tiles show information on pulse, blood oxygen saturation, and stress combined with a button for breathing exercises. The order and content of the tiles can be customized in the smartphone app.

Swiping from top to bottom opens the notifications menu. Notifications are listed there in chronological order and sorted by app. Swiping from bottom to top opens the short menu with access to media control and various modes such as do not disturb or energy-saving mode.

Telephony and notifications - Only short replies on the Redmi Watch 4

The Mi Fitness app can be used to select which programs can send notifications to the smartwatch. In the test, the notifications arrive reliably on the Redmi Watch 4. However, long messages such as emails are truncated. In addition, the smartwatch cannot display images and only a few emojis. Replies are only possible with the help of short replies - they can be customized in the app.

It is possible to make calls with the Redmi Watch 4, which has a speaker and microphone. However, due to the lack of its own wireless connection, a paired smartphone must always be within Bluetooth range. The smartwatch can display call lists, and numbers can be entered via a numeric keypad. However, contacts are not synchronized with the smartphone. You have to store your own favorite contacts in the Mi Fitness app.

Making calls with the Redmi Watch 4 is something for emergencies and short calls. The speaker is loud without being too distracting. There is no background noise, but the watch wearer's voice is sometimes very choppy, and syllables are sometimes slurred.

Voice assistant - Xiaomi does without despite capable hardware

Although the Redmi Watch 4 has a built-in microphone and speaker, Xiaomi does not have a voice assistant. Due to the lack of an app store, it cannot be installed later.

Health and fitness - Redmi Watch 4 with vitality value

The Redmi Watch 4's health data is collected in the Mi Fitness app. It can be synchronized with Google Fit, Strava, and Suunto. The smartwatch can measure heart rate, blood oxygen saturation, and stress. The stress level is indicated with a number between 0 and 100.

In addition, the software offers a classification into four phases, which are color-coded and marked with emojis. The timeline displays the stress level throughout the day. The app also provides a daily summary with minimum, maximum, and average values.

A special feature of the Redmi Watch 4 is the vitality value. This value includes age, resting heart rate, maximum heart rate, and training data from the past seven days. Vitality points are collected through exercise and training, with intensive training giving more points. According to Xiaomi, the value should ideally be over 100 because then the WHO exercise targets are achieved. A maximum of 80 points can be collected per day.

Activity goals - The Redmi Watch 4 does not always count

The Redmi Watch 4 shows daily activity with the help of semicircles. These represent calories burned, steps taken, and standing per hour. Progress can be tracked not only via the semicircles but also using values. The display is provided both on the smartwatch itself and in the Mi Fitness app.

The app also provides an overview of the values for the week and an average value for the respective category. In addition to the steps, the distance covered is also displayed. However, there is no information on altitude meters or floors.

However, the recording of activity is often incorrect in the test. In some cases, the smartwatch only shows 1000 steps after a hike, and the Redmi Watch 4 does not record any steps or calories burned over several days of continuous wear, although time spent standing is recorded. The detection of standing does not leave a good impression either. The reminder to move often appears a few minutes after getting up from the desk.

Heart rate, heart rhythm and blood oxygen saturation

To better classify the measured values of Redmi Watch 4, we compare them with those of reference devices. To measure the heart rate, we took the Xiaomi smartwatch on a bike ride together with a Polar H10 chest strap.

When measuring the resting heart rate before the sports session, the devices are quite consistent. The value of the Redmi Watch 4 is two beats above that of the chest strap, the deviation is 2.94 percent. We measured the power pulse at three different times. The deviation between the devices averages 11.99 percent. The measured values of the smartwatch are lower than those of the chest strap for all three measurements.

The difference is smaller when measuring blood oxygen saturation. The average deviation from three measurements is 2.02 percent. The measured values of the Redmi Watch 4 are always lower than those of the reference device. In this case, this is a Braun Pulse Oximeter 1.

Overall, the measured values of the Redmi Watch 4 are okay. However, athletes should use a different device for accurate heart rate measurement during training. The Amazfit Active shows that things can be better in the price range.

Heart rate measurement Xiaomi Redmi Watch 4
Heart rate measurement Xiaomi Redmi Watch 4
Heart rate measurement Polar H10 chest strap
Heart rate measurement Polar H10 chest strap

Sleep tracking - Xiaomi smartwatch shows sleeping animal

The Redmi Watch 4's sleep tracking is impressive. The software shows the total sleep time and duration for the individual sleep phases. The app differentiates between deep, light, and REM sleep. A time is displayed for each phase, and the software also shows the percentage of total sleep and the ratio to the recommended values.

The progression of the phases is also displayed graphically on a timeline. Waking phases are also reliably detected. If the detailed sleep analysis is selected, the smartwatch also measures the average heart rate and the average blood oxygen saturation. The saturation also has an impact on breathing points, which are awarded by the software.

Total sleep is also assessed with a numerical value between 0 and 100. In addition, the value is compared with those of other users in the same age group. The values can be displayed not only for one day but also for weeks and months.

If sleep is measured over a longer period of time, the Mi Fitness app assigns a sleep animal. This categorizes sleep patterns. The sleep rhythm, sleep continuity, stress, and movement before going to bed are analyzed. The software also makes recommendations on how to organize your daily routine.

The Redmi Watch 4 also has a smart alarm clock. This uses the collected data to wake the wearer from a light sleep if possible. However, the selectable period is short at ten minutes.

Training recording - Large selection with the Redmi Watch 4

The Xiaomi Redmi Watch 4 can track over 150 types of sports. Different targets can be set for different sports, for distances, times, and calories burned. Training alarms can also be set when a certain heart rate is reached or after a certain distance. For certain sports - such as jogging - the smartwatch also supports a warm-up program and interval training.

Jogging is a focal point of the training sessions. In this discipline, the Redmi Watch 4 also offers an AI pacer that runs the average pace of previous workouts. In addition, the smartwatch comes with ten pre-installed training plans tailored to runners of different performance levels.

Completed workouts can be viewed both on the smartwatch itself and in the Mi Fitness app. The Redmi Watch 4 records the route and, in addition to heart rate and distance, provides other training-specific values, such as stride length and cadence when walking. The software also estimates the training effect and provides information on recovery time.

The Redmi Watch 4 can also automatically recognize and record workouts. However, this does not always work reliably in the test. Sometimes workouts are not recognized at all, although the sport is recognized on other days, and sometimes the recording only starts with a long delay.

GPS and navigation - Precise location with the Redmi Watch

The Redmi Watch 4 is GNSS-capable and supports all common satellite systems - which is not a matter of course in this price range. In addition, tracking on a bike lap together with a Garmin Venu 2 proves to be accurate.

The connection takes a little longer in everyday use but it is wonderfully stable. We did not experience any connection interruptions during the test. Recorded routes can only be exported via a detour, for example via synchronization with Strava. It is not possible to import routes for training.

GNSS measurement: Circumnavigation of the lake
GNSS measurement: Circumnavigation of the lake
GNSS measurement: Turning point
GNSS measurement: Turning point
GNSS measurement: Summary
GNSS measurement: Summary

Display - Large AMOLED panel for the Redmi Watch 4

Subpixel structure
Subpixel structure

The Redmi Watch 4's 1.97-inch AMOLED panel makes a good impression. We measured a maximum brightness of 555 cd/m² with the ambient light sensor activated, making the smartwatch easy to read even in the sun. The resolution is also good, with content and fonts displayed clearly. Thanks to the technology used, the display also impresses with a perfect black level and crisp contrasts.

During our measurements, we noticed a flickering with a frequency of 166 Hz. The ambient light sensor adjusts quickly and appropriately; we didn't have to readjust brightness in everyday use. The always-on display is also a good solution. A schedule can be created for the function, or alternatively, a smart detection should ensure that screen stays dark at night.

Xiaomi Redmi Watch 4Amazfit ActiveAmazfit GTS 4Huawei Watch Fit Special EditionXiaomi Smart Band 7 ProOukitel BT20
Response Times
PWM Frequency
Brightness middle
Black Level *
Total Average (Program / Settings)
-15% / -15%
-22% / -22%
-39% / -39%
-18% / -18%
-21% / -21%

* ... smaller is better

Screen Flickering / PWM (Pulse-Width Modulation)

To dim the screen, some notebooks will simply cycle the backlight on and off in rapid succession - a method called Pulse Width Modulation (PWM) . This cycling frequency should ideally be undetectable to the human eye. If said frequency is too low, users with sensitive eyes may experience strain or headaches or even notice the flickering altogether.
Screen flickering / PWM detected 166 Hz

The display backlight flickers at 166 Hz (worst case, e.g., utilizing PWM) .

The frequency of 166 Hz is relatively low, so sensitive users will likely notice flickering and experience eyestrain at the stated brightness setting and below.

In comparison: 53 % of all tested devices do not use PWM to dim the display. If PWM was detected, an average of 17900 (minimum: 5 - maximum: 3846000) Hz was measured.

Performance and battery life - Xiaomi smartwatch with minor stutters

Xiaomi does not provide any information on the SiP installed in the Redmi Watch 4, and as no browser can be installed, no benchmark measurements are possible. In everyday use, the performance is okay: apps and menus open quickly, but there are small jerks when switching between cards. After pressing the crown, the smartwatch sometimes takes a second to execute the command.

There is also no information on the built-in memory. However, this can hardly be used. Music and maps cannot be saved locally, and there is no app store.

Battery life - Redmi Watch 4 runs for a very long time

Xiaomi advertises a battery life of up to 20 days, but many functions have to be deactivated to achieve this. We permanently activated all measurements in the test, as well as the automatic training detection, allowed all app notifications, and also used the always-on display. This puts a maximum strain on the battery.

Despite this, the Redmi Watch 4 managed a runtime of nine days in the test, including short workouts. With AoD deactivated, we managed 12 days of use without recharging. Charging is possible with a proprietary cable that is magnetically attached to the underside of the watch. The smartwatch charges from 5 to 85 percent in one hour. It takes around 80 minutes for a full charge.


+ high-quality workmanship
+ large, bright display
+ versatile tracking
+ own GNSS connection
+ long battery life


- no voice assistant
- some software bugs
- no NFC
- heart rate measurement partly inaccurate

Verdict - The Redmi Watch 4 is slowed down by the software

In review: Xiaomi Redmi Watch 4, test device provided by Xiaomi Germany.
In review: Xiaomi Redmi Watch 4, test device provided by Xiaomi Germany.

The Xiaomi Redmi Watch 4 has two faces. On the one hand, it is a beautifully crafted, stylish smartwatch. The fine aluminum frame and the large, bright AMOLED display are highlights in this price range. With a brightness sensor and integrated satellite connection, the Xiaomi smartwatch clearly sets itself apart from inexpensive fitness trackers. The Redmi Watch 4 also boasts a very good battery life.

The range of functions of the smartwatch is also impressive. With its diverse settings, the Redmi Watch 4 is more impressive during training than in everyday use. The display of images and emojis could be improved, as could the reply options. It is also incomprehensible that Xiaomi does not have a voice assistant despite the speaker and microphone.

The software of the Redmi Watch 4 is unreliable and greatly disrupts the overall picture of the chic smartwatch.

However, the biggest annoyance of the Redmi Watch 4 is the software, which still had a few bugs at the time of testing. The smartwatch keeps restarting from time to time, which is still bearable. More annoying, however, is that steps and other activities are not reliably recorded and, above all, the smartwatch repeatedly displays the wrong time even though it is connected to the smartphone. This basic function of a wristwatch simply has to be reliable.

Similarly chic and functional is the Amazfit Active, much more accurate in the measurements of body values but visually in a different league is the Fitbit Charge 6.

Price and availability

The smartwatch is sold at many major retailers, such as Amazon US. Xiaomi also sells the Redmi Watch 4 in its online store.


The present review sample was made available to the author as a loan by the manufacturer or a shop for the purposes of review. The lender had no influence on this review, nor did the manufacturer receive a copy of this review before publication. There was no obligation to publish this review.


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> Expert Reviews and News on Laptops, Smartphones and Tech Innovations > Reviews > Xiaomi Redmi Watch 4 smartwatch review - Beautiful, but with software flaws
Benedikt Winkel, 2024-03-30 (Update: 2024-03-30)