Xiaomi Mi Smart Band 4 review: a capable budget fitness tracker

I’ve been using Xiaomi’s Mi Bands on and off for the last four years, and in that time, the brand’s budget fitness bands have come a long way. The latest device in the lineup is the Mi Smart Band 4, which brings with it a few upgrades – it adds a colour display for the first time, along with a swim tracking feature. Xiaomi has also added ‘Smart’ to the name this time around, which is a rather obvious and unnecessary addition. The Mi Smart Band 4 also comes with a higher price tag compared to previous-gen devices, but is still affordable as far as fitness bands go. I’ve been wearing it pretty much 24 / 7 over the last couple of weeks, and here’s what you need to know if you plan to pick one up for yourself.

Design and display

The Mi Smart Band 4 retains the same pill-shaped module of previous generation Mi Bands, but increases the size of the display to 0.95-inches (the Mi Band 3 featured a 0.78-inch display). There’s a single wake/back button placed below it, and the display itself is touch sensitive, registering swipes and taps easily. The screen is an AMOLED panel this time around, and comes with a resolution of 120 x 240 inches. The display is fairly bright with a maximum brightness of 400 nits, making it visible outdoors as well. You won’t find any Gorilla Glass protection, but there is 2.5D tempered glass which managed to remain unscathed during my testing period. Xiaomi has also added an anti-fingerprint coating, and while it still picked up smudges, they aren’t noticeable unless you look at the screen in direct light.

The quality of the display is excellent for a budget fitness tracker, with vibrant colours and inky blacks. There are three display styles to choose from on the band itself, and if you want access to more, you can head to the Mi Fit app where there are 60+ options available to download and sync. There’s also the option to create a custom display by using your own image. There are three templates to choose from, and once you select the image of your choice, you can crop and rotate it to get the perfect background. The screen also offers a night mode feature, which lowers the brightness at night and turns off the colour. You can schedule night mode timings from within the Mi Fit app.

As for the other elements, the heart rate sensor is in its usual location at the base of the module. There are metallic pogo pins to connect to the custom charging cradle as well. The removable wrist strap is made of thermoplastic polyurethane, and features a nice matte finish which looks more premium than previous generation bands. Xiaomi says that the Mi Smart Band 4 straps are compatible with the Mi Band 3 as well, so you can purchase additional straps from Xiaomi’s website and swap them out. The band features a water-resistance rating of 5ATM, which means you can take it for a swim or use it in the shower.

Interface and features

By default, the Mi Smart Band 4 shows you a homescreen with the time and date, battery indicator and your step count. Swiping to the right or left will bring up music controls, allowing you to play/pause or change tracks playing on your smartphone. Swiping up or down takes you through the main menu, with screens for activity status, heart rate, notifications, workouts, weather and more. You can rearrange the order of these screens from the app, and remove any screens you don’t want to see.

The workout mode lets you pick from six activities – treadmill, exercise, outdoor running, cycling, walking and pool swimming. The swim tracking feature records 12 data sets according to Xiaomi, including swimming pace, stroke count and distance, among others. In the ‘More’ section, you can access DND settings, alarms, stopwatch, music, timer, silent mode and the wider settings menu. Strangely, the DND options only allow you to turn on/off DND manually, or enable it automatically when you fall asleep. There’s no option to sync it to your phone’s DND settings, so I ended up getting notification alerts even after DND was enabled on my phone. Notably, the Mi Band 3 allowed you to schedule DND timings from the Mi Fit app, and this is missing on the Mi Smart Band 4.

The app comes with the usual feature set, letting you set up alerts for incoming calls, app notifications, SMS, reminders, idle alerts and goal notifications, among others. You can customise heart rate detection from here, choosing from automatic heart rate detection, sleep assistant or both. Enabling the latter gives you better sleep data, but impacts battery life in the process. You can also choose the detection frequency, with intervals of 1, 5, 10 and 30 minutes. Additionally, you can turn on activity detection, which increases the detection frequency when you’re exercising.

Usage experience

The Mi Smart Band 4 is lightweight and comfortable, and didn’t bother me at all while sleeping either. The larger display displays more text for notifications, and app names are listed on top so you know where the notification is coming from too.

When it comes to step tracking, I’ve always found Xiaomi’s Mi Bands to be pretty accurate, and the Mi Smart Band 4 is no different. However, if you’re specifically looking to log your outdoor workouts, the lack of inbuilt GPS is an issue. This means that the Mi Smart Band 4 can’t track distance accurately. There is a workaround, which requires you to carry your phone with you, allowing the Mi Fit app access to your phone’s GPS. If you’re looking for a fitness band to specifically track outdoor runs or walks however, I’d recommend opting for a GPS-enabled device.

The sleep monitoring feature gives you a decent idea of your sleep patterns, but there are issues with logging awake times. With a toddler who’s a bad sleeper, I wake up multiple times at night, and the Mi Fit app tends to log this as light sleep. Another glitch I found was with the idle alerts, which the band frequently sent me even after I had walked a few steps.

The battery life is the star of the Mi Smart Band 4. Xiaomi estimates it to be about 20 days. In my testing period, after using it for 12 days I had about 38 percent of battery left over, which is excellent. The charging cradle this time around isn’t of the best quality though – the band doesn’t fit inside well, and popped out a few times too. I preferred the previous charging cradle designs which opted for a slide-in mechanism that was more secure.


At its asking price of Rs 2,299, the Mi Smart Band 4 is one of the best fitness trackers you can currently buy. With its colour display, waterproof build, swim tracking and excellent battery life, it carries forward the legacy of previous Mi Band fitness trackers, while adding some much-needed upgrades. The lack of GPS doesn’t make this ideal for serious fitness tracking, but for the average user who wants to track their daily activity while being able to quickly check notifictions, you can’t beat the Mi Smart Band 4.

Pricebaba’s rating: 8 / 10

What works:

  • Vibrant AMOLED display
  • Excellent battery life
  • Swim tracking
  • Accurate pedometer

What doesn’t:

  • No inbuilt GPS
  • Sleep monitoring isn’t very accurate
  • Charging cradle is flimsy
Ketaki Bhojnagarwala

Ketaki has over 10 years experience writing on tech, having worked at the Hindu Business Line and 91mobiles earlier. When she's not editing copies or reviewing the latest gadgets, she spends her time binge-watching Netflix and reading fantasy fiction.