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Lifewire / Erika Rawes
Excellent battery life
Inaccurate step counter
Some activity tracking imprecise
The Mi Smart Band 4 offers an affordable and intelligent fitness tracker with impressive battery life.
We purchased the Xiaomi Mi Smart Band 4 so our expert reviewer could thoroughly test and assess it. Keep reading for our full product review.
Budget fitness trackers like the Xiaomi Mi Smart Band 4 tend to be hit or miss, with some budget models providing accurate data and useful features, and others serving as basic monitors and pedometers with a few additional features that may or may not work well. I tested the Xiaomi Mi Smart Band 4 for two weeks to see how it performs compared to other budget and mid-range fitness trackers on the market.
The Xiaomi Mi Smart Band 4 is just the right size—it doesn’t overpower a small wrist, and it doesn’t look too small on a larger wrist. It’s stylish and simple, with a rounded screen and a rubberized adjustable band. The tracker is removable, and you can switch out the band and purchase other styles and color options. You can find a 10-pack of replacement bands in different colors on Amazon for around $10 to $15.
The tempered glass screen is clear and vivid, with a fingerprint resistant coating to help maintain a clean appearance.
One area where the Xiaomi Mi 4 really shines is its screen, which is a 0.95-inch full color AMOLED display with 400 nits max brightness. The tempered glass screen is clear and vivid, with a fingerprint resistant coating to help maintain a clean appearance. You can see a huge difference between the screen quality on the Mi Band 4 and its predecessor, the Mi Band 3, which was too dim and difficult to read. The Mi Band 4 is clear and bright, and you can easily read the display from a distance. The interface is well designed too, and you can choose between a large library of different watch faces. I chose a watch face that includes a small image of a unicorn. You can also customize your watch face and add a picture from your photo library.
The Xiaomi Mi Band 4 is water resistant with a 5 ATM rating. This means the band can go in up to 50 meters of water for up to 10 minutes, and it can tolerate shallow water activities like swimming. You can comfortably shower with the band, wear it in the rain, or wear it while you’re drenched in sweat. It doesn’t feel too hot on the wrist either.
The adjustable band is about a quarter of an inch in width, and it has rounded edges for maximum comfort. Instead of having a prong that slides through the size adjustment holes, it has a small button that presses into the sizing holes. I find the button design more comfortable and easier to take on and off than a fitness tracker with a prong.
The Mi Band 4 adjusts between 155 to 216 mm, so it fits most wrists snugly without leaving any marks. It doesn’t dig into the skin, so I could wear it while typing. It’s also surprisingly comfortable to wear while sleeping and during exercise. It allows for a full range of motion with my hand, and I can perform all exercises while wearing it, including pushups, which can sometimes be uncomfortable with other trackers that have a thicker band.
The Mi Band 4 has a responsive touch screen that doesn’t lag when switching between screens or loading data. It has an impressive feature set for a fitness tracker in this price range, although some of the tools aren’t always pinpoint accurate, and you won’t get as many perks as you’d get with a fitness tracker in a higher price range. All in all, I was impressed with the fitness tracker’s overall performance.
It has workout modes for using a treadmill, general exercise, outdoor running,cycling, walking, and swimming that you can set up right on the watch’s main screen. It has 24/7 heart rate monitoring, sleep tracking, and notifications for calls, texts, and a few apps (like Skype and your Calendar). You can even customize the vibration settings for different types of alerts and notifications. When you receive a call, you can deny the call from the fitness tracker. You can also read texts right on the tracker’s screen, although emojis and Apple Memojis won’t display.
On the downside, the step counter overstates steps, and it’ll sometimes track other hand movements as steps, like typing or swinging my arm. The heart rate monitor was dramatically inaccurate by as much as 15 beats per minute compared to a chest strap. However, the accuracy of the heart monitor improved when I placed the tracker in a better location on my wrist. The tracker lacks built-in GPS, and it uses your phone’s GPS for location based tracking.
The Mi Fit app is somewhat basic, but it provides useful health and fitness information. Some functions, like automatic monitoring, aren’t as easy to find in the app as others, but overall the basic app serves its purpose. As with most fitness trackers, you can set alarms, set event reminders, and share your fitness info. You can view historical data on your heart rate, workouts, steps, and calories burned. You can track your sleep, including deep sleep, light sleep, hours slept, and more.
In addition to customizing settings and widgets and tracking your data, the Mi Fit app works with other products like the Mi Composition scale, which can provide a more comprehensive experience, including body weight and balance data.
The Mi Band 4’s battery is phenomenal, as the 135 mAh battery lasts for up to 20 days. Options within the app for things like better sleep monitoring and heart monitoring can greatly reduce battery life, however, the app will warn you about that when selecting such options.
I took full advantage of the tracker’s features over a two week period, and I was at about 10% battery at the end of the two weeks.
The 135 mAh battery lasts for up to 20 days.
Pressing the “find my band” button 30 times (which vibrates the band) reduced the battery by only one percent, so this device makes incredibly efficient use of its battery.
The only negative about the battery is when it comes time to charge the device. You have to remove the tracker from the band and place it onto a mini charging station. It’s somewhat difficult to remove from the band, and you have to kind of wiggle it out of the band. The unit also fits snugly into the charging station, so you have to gently force the Mi 4 Tracker into the charging station to ensure it’s properly charging. Once you achieve that, it takes about one hour and 45 minutes to reach a full charge.
The Xiaomi Mi Smart Band 4 is incredibly affordable, selling for $29 on Amazon. The next gen band, the Mi Band 5, is now hitting the market, which is lowering the price of the fourth generation model. The Mi Band 4 isn’t perfect by any means, and it won’t provide the same experience that you’d get with a tracker that costs hundreds of dollars, but it’s a steal at its price point.
For a light user, the Xiaomi Mi Smart Band 4 will provide a similar experience to the Fitbit Charge 3, and for much less cash. The Mi Band 4 sells for less than $30, while the Charge 3 (view on Amazon) sells for closer to $100. The Mi Band 4 even has a color display, which the Fitbit Charge 3 lacks. If you want a budget tracker with better accuracy, the Charge 3 is probably the way to go. If you just want to try out a fitness tracker, the Mi Band 4 is a good choice.
Impressive, especially for the price.
The Xiaomi Mi Smart Band 4 offers a lot of features for a little bit of cash.