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Xiaomi Mi Band 4 review: At this price, it’s essentially flawless

Our Rating :
£39.90 from
Price when reviewed : £35
inc. VAT

You get a whole lot of wearable for your £35, with big improvements on the Mi Band 3


  • Real improvements over the Mi Band 3
  • Better run tracking
  • Colour screen is excellent
  • Incredible battery life


  • The Mi Fit app is a weak link

Good news and bad news for fans of the cheap and extremely cheerful Xiaomi Mi Band 3. The bad news is that the Mi Band 4 is 29.6% more expensive than its predecessor. The good news is that means it’s still only £35.

READ NEXT: Honor Band 5 review

Xiaomi Mi Band 4 review: What you need to know

It turns out that this extra £8 can buy you an awful lot of features, though. The screen is bigger, higher resolution and in colour now for a start. It’ll also attempt to track runs via connected GPS which should improve the accuracy no end (guessing distances traveled by step counting and stride length is flakey to say the least). And, while its predecessor was waterproof, but useless to swimmers, this one actively tracks swims making it an essential companion at the pool.

Despite these improvements, Xiaomi says the battery life is the same impressive 20 days, too. That’s because the battery cell has also grown a little, from 110mAh in the Mi Band 3 to 135mAh in the Mi Band 4.

Xiaomi Mi Band 4 review: Price and competition

When we reviewed the Xiaomi Mi Band 3, cheap fitness trackers were a rarity. Now they’re far more common.

Suddenly, the £35 Mi Band 4 doesn’t look so amazing, because Huawei has its own cheap and cheerful rival in the form of the £30 Honor Band 5. Of course, if you really want to pay more, then the Fitbit Inspire is available for £50, but you’ll have to pay £90 for the version with a heart-rate tracker.

None of these come with built-in GPS, of course, but gone are the days when paying for such location tracking would send the price hurtling into three figures. The Amazfit Bip is a GPS-packed smartwatch with a ridiculous battery life for £50, and the Huawei Band 3 Pro does the same and costs a very reasonable £80.

Xiaomi Mi Band 4 review: Design

The Xiaomi Mi Band 4 is pretty similar looking to its predecessor, at a glance. Both are small black lozenges which sit securely within a rubber wrist band when in use and in a small charging dock when not. Despite the larger display, the Mi Band 4 is even compatible with Mi Band 3 straps, which is both impressive in itself and decent of Xiaomi not to make returning buyers start afresh.

The screen isn’t actually as big as it looks in the attached photos, by the way. It simply has a black background that blends in with the rest of its plastic housing. It is, however, big enough that you can clearly read the information you need at a glance, and it’s bright, vibrant and colourful, too. WhatsApp messages can be a bit tricky to make out but to Xiaomi’s credit the Band 4 does display the whole message (over multiple screens if necessary) instead of truncating it like some of its rivals.

There are no physical buttons. Instead, everything is controlled by swiping of the touchscreen and the capacitive home button that sits below it. Just wake it up with a tap of the virtual button and then swipe away to get the data you want.

I’m not a big fan of button-free wearables for tracking workouts, personally. The thing about touchscreens is that they tend to react poorly to water, as anybody who has ever tried to text in the rain will tell you. And exercise tends to involve things getting wet – either through sweat, or a little rain as you enter your final sprint.

It’s a little bulky, too, protruding a good 10.8mm from the wrist. That may not sound like much, but remember most smartphones are around the 8mm mark and imagine how that looks – especially on a device with a long and thin profile, like this.

But you are paying £35, and considering what this design means in terms of stamina and performance, I think it’s a compromise that’s ultimately worth making.

Xiaomi Mi Band 4 review: Performance

While reviewing the Xiaomi Mi Band 4, I’ve had various other wearables on my opposite wrist for comparison. A quick sense check: this morning, the Mi Band 4 says I’ve done 2,932 steps, while the Garmin Forerunner 245 reckons 2,965 which is surprisingly close.

But even if it wasn’t, it wouldn’t be a big deal – the exact number of steps doesn’t matter per se, as long as the wearable is consistent with itself. All you really need to know is “did I do more or fewer steps than yesterday, and is it a suitably high number that I can be pleased with myself?”

Still, the Mi Band 3 already did step tracking. The big advancement in performance terms is the connected GPS, where the wearable can utilise the phone’s location tracking data. Here, of course, you’re reliant on your phone and when I tested it I was at the mercy of my Huawei P20 Pro’s aggressive battery-saving algorithms. Despite this, it performed well, measuring a distance of 3.49km compared to the Polar M430’s 3.59km.

It’s best not to look too closely at the detail, though. Zooming in on the map suggests I was so enamoured by the proximity of Cats Protection Mitcham that I burst off the pavement and into the industrial park.

But it’s important not to be too critical: at the risk of repeating myself, this is a £35 fitness tracker, not a £200 running watch. To come this close to a dedicated running watch is pretty good going.

Oh, and speaking of ‘good going’, the battery in the Mi Band 4 just runs and runs. The 20 days quoted by Xiaomi may be pessimistic, in fact, depending on your usage. I’ve had this on my review to-do pile for a while, and when I pulled it out of my bag after a month of delays it still had over 30% of its battery left.

Xiaomi Mi Band 4 review: App

So far, so good then. The biggest weakness, for me, is the Xiaomi Mi Fit app, which is pretty bare-bones stuff. It’s also not the most user-friendly experience I’ve ever had, and tracking down past running data was a bit of a chore. Once found, the data is nowhere near as comprehensive as the sort you might find on Garmin Connect or Polar Flow, either.

That said, once you get past the initial confusion there’s some interesting data in there, especially on the sleep tracking side of things, where the app will not just show you the information, but tell you how that compares to others. It also supplies practical tips on how to have more restful nights.

But there are two things that hold it back. First, Xiaomi is primarily still a Chinese company, which means that you’re clearly less likely to find your friends using the app, unless all your friends live in China. If your fitness regime is motivated by friendly competition then this is clearly a big issue.

Second, its Chinese roots are clear in the tiny list of apps you can connect: WeChat and Google Fit. No Strava, no Runkeeper and no MyFitnessPal. These two things combine to make spending twice as much on a Fitbit Inspire HR seem a reasonable option.

Xiaomi Mi Band 4 review: Verdict

That feels like nitpicking though: as a product, it’s extremely hard to quibble with the Xiaomi Mi Band 4, especially when my concerns about the app also apply to the similarly priced Honor Band 5.

The Mi Band 3 was a bargain at £27, and the Mi Band 4 certainly has £8 worth of extra value. From its larger, more eye-catching screen to its ability to track runs using your phone’s GPS, the Mi Band 4 is an extremely worthy follow up that’s definitely worth a look for budget-conscious consumers.

Is it worth buying ahead of the Honor Band 5, though? Honestly, that comes down to personal preference, because each has one minor advantage over the other. While the Honor Band 5 can measure blood oxygen saturation (SpO2), the Xiaomi Mi Band 4’s battery is 35mAh larger. One more (fairly unnessesary) sensor or an even longer battery life? If I were you, I’d just take a look at whichever is cheaper on the day and buy that. But both come strongly recommended.