Mi Smart Band 4 is an affordable fitness band from Xiaomi. With this, the fourth iteration of the Mi Band, Xiaomi has introduced a colour display and swim tracking, and still claims to offer 20-day battery life. The Mi Band lineup began with a product that didn't even have a display and now we get a device with an AMOLED colour display and lots of watch faces, which are nice to have. The Mi Smart Band 4 costs a little more than the Mi Band 3, but are its new features worth the asking price? We used it for a week to find out.
Mi Smart Band 4 design
The Mi Smart Band 4 has all its electronics in a plastic capsule that fits snugly into a silicone band. The display is on the capsule, and a single capacitive button is below the screen. The base of the capsule has the heart rate sensor and pins for charging. To charge the Mi Smart Band 4, you need to take the capsule out of the band and place it in its charger.
The Mi Smart Band 4 capsule does not fit into the charger very well. It kept popping out before eventually slotting in, which was quite annoying. This is the biggest design weakness of this product.
The Mi Smart Band 4 is comfortable to wear for long hours. We wore it throughout the day and while sleeping at night, and never found it to be in the way. The band also offers a secure fit.
The 0.95-inch AMOLED display of the Mi Smart Band 4 is a great feature. Text looks crisp and colours look nice too. We didn't have any issues reading it under direct sunlight, although we found the font for notifications to be a bit too thin.
The touchscreen and the capacitive button below the display are responsive. We think the user interface of the Mi Smart Band 4 is quite good. You can swipe up or down to cycle through screens, which show details of your workout, notifications, heart rate, etc. You can customise this list using the Mi Fit app on your paired phone. If you swipe left or right, you'll see the music player. The music controls worked well, but it did take a couple of seconds to load the name of the song and playback controls and we think that's too slow.
Mi Smart Band 4 performance and battery life
The Mi Smart Band 4 has a lot of useful features such as the ability to track different types of workouts including swimming, sleep tracking, continuous heart rate monitoring, and notifications are displayed too. Our biggest problem with this device was that most of the useful features were disabled by default and we had to manually enable them in the app.
For example, sleep assistant (which helps get precise sleep data), notifications, and the option to wake the display when you lift your wrist were all disabled when we started using this device. The last one in particular is such a basic feature that it really should be the default behaviour. These settings are not very easy to find either, which compounds the problem.
It's important to note that when we enabled each one of these features, we saw a warning message informing us that battery life might be reduced because of it. However, potentially missing out on some of the Mi Smart Band 4's best features is not a reasonable trade-off, in our opinion.
As for performance and tracking accuracy, we put the Mi Smart Band 4 through our standard set of tests. First we went for a 1km run measured using GPS on our phone, and then noted the distance measured by the Mi Smart Band 4. The Xiaomi wearable does not have in-built GPS, so its distance tracking is not likely to be very accurate. Xiaomi lets you use your phone's GPS to track the run if you allow Mi Fit access to your location. For this test we disabled Mi Fit's location access. The Mi Smart Band 4 logged 1.3km as compared to the 1km logged on the phone. We tried the same test again after granting location access to Mi Fit, and the result was 1.11km logged. The second result is acceptable, but it's more to do with the accuracy of the phone's GPS as opposed to the accuracy of Mi Band's tracking.
We also ran our standard step tracking test on the Mi Smart Band 4, in which we walked 1,000 steps and counted them manually. We saw that the Mi Smart Band 4 had logged 996 steps, which is excellent.
Mi Smart Band 4 has an exercise tracking mode too. We used this for our gym sessions and found it to be reasonably accurate. Its heart rate tracking feature was satisfactory too, and the results were pretty good considering that the Mi Smart Band 4's price in India is less than Rs. 2,500.
Sleep tracking data was accurate for the most part, except for the “time awake” metric displayed in the Mi Fit app. We noticed that it would show time awake as 0 minutes even though we distinctly remember waking up multiple times through the night.
The Mi Smart Band 4 is rated swim-proof and can track your swimming workouts too. We were unable to test this feature during the review period but we did take the product into the shower every day, and it emerged unscathed.
Xiaomi claims that the Mi Smart Band 4 has a battery life of around 20 days. We used the device for a week and found that the battery went down to 63 percent (remaining) in that time. If you enable all optional features such as precise sleep tracking, the battery drains faster. Even then, you can expect the Mi Smart Band 4's battery to last for over two weeks on a single charge.
Mi Smart Band 4 companion app
We've always appreciated the quality of the Mi Fit app and often noted how it's much better than the companion apps for several fitness bands priced higher than Xiaomi's Mi Band lineup. Our thoughts on the Mi Fit app remain largely the same even now. We think it looks good, and largely makes it easy to find the data you need. A couple of data points, such as historical data for exercise and running, were slightly hard to find because they weren't in an obvious spot. However, this is a minor quibble.
We'd have liked to have the Mi Smart Band 4 displayed on the main screen instead of under the Profile tab. This would allow us to modify preferences and watch faces for the wearable more quickly. Speaking of which, there are lots of watch faces for Mi Smart Band 4 and we liked quite a few of them. There are a lot of watch faces here and you can even create custom watch faces with photos from your smartphone. For custom watch faces, only the background photo can be changed but you do have three display styles for a bit a variety in terms of what's displayed on screen.
Another nice touch is the ability to customise the vibration pattern for the Mi Smart Band 4. By default the wearable vibrates a bit too strongly for our liking. The device has the ability to show app notifications, and it even shows caller ID and previews for text messages, emails, and all third-party app alerts. If you get too many notifications, you should set a subtle vibration pattern on the Mi Smart Band 4. This one tweak turned notifications from an annoyance into a useful feature. However, you can't set a different vibration pattern for different apps or people.
The Mi Smart Band 4 is another solid product in the Mi Band lineup. We loved its display, comfort, and workout tracking accuracy. The Mi Fit app is still quite good, and the ability to set custom vibration patterns for notifications is a godsend. However, the Mi Smart Band 4's default settings leave several essential features disabled. It's also a real shame that Xiaomi chose an inferior proprietary charger this time around. If you can live with these annoyances, the Mi Smart Band 4 is one of the best low-cost fitness bands you can buy right now, and is well worth its asking price of Rs. 2,299.
- Accurate activity tracking
- Vibrant display
- Custom vibration patterns for notifications
- Decent battery life
- Proprietary, ill-fitting charger
- Several tracking features disabled by default
Ratings (out of 5)
- Design: 3.5
- Tracking: 4
- Companion app: 4
- Battery life: 4.5
- Overall: 4