What’s up with the battery life of smartwatches?

Smartwatches are a smartphone’s best friend – I say this with total conviction. Some people use them to track their sleep, others their training and still others rely on them for listening to music on the go. These high-tech features are all well and good. But if you ask me, they’re still quite gimmicky.

So why do I bother wearing a smartwatch? Notifications. My phone’s been on silent for almost ten years. Every WhatsApp message, every call and every reminder goes right to my wrist. If you ask me, a smartwatch is the most discreet way to stay up to date. After all, I can’t accidentally (cough cough) start scrolling through Instagram or TikTok on my watch when all I wanted to do was check a notification. In a way, it’s a kind of digital detox.

The smartwatch: a constant companion – in theory

For me, not wearing a smartwatch is simply not an option. My current companion is the Google Pixel Watch 2. Unfortunately, just about every smartwatch needs daily charging. The current Google Pixel Watch, for example, has a battery life of 24 hours. Samsung’s and Apple’s models fare a bit better, but they’re still not what I’d call good.

The big smartwatch manufacturers advertise a battery life of days. Sounds unbelievable! The Samsung Galaxy Watch 5 Pro promises roughly 80 hours of runtime for about 240 francs. In practice, however, with all its features and always-on display (AOD) activated, it’s closer to 2-3 days. And for me, AOD is a non-negotiable.

When it comes to Apple watches, the situation looks even worse. The Apple Watch Ultra 2, which costs over 700 francs, promises just 36 hours of battery life with everyday use. So even if you’re just going away for the weekend – let alone for longer – you’d better remember to bring your smartwatch charger with you. Forget it, and your smartwatch will quickly turn into nothing more than an expensive bracelet.

If that doesn’t sound good to you, there are smartwatches out there with a better battery life.

These smartwatches boast a really long battery life

The good news is you don’t have to look far to find a smartwatch with decent endurance. There are a number of fitness trackers, such as the Oppo Watch Free, the Huawei Fit 2 or the Xiaomi Smart Band 7 Pro, which offer a solid one to two weeks of battery.

Alas, fitness trackers have a reduced range of functions, typically missing features such as NFC, LTE or a sophisticated operating system like Wear OS.

But there are also fully fledged smartwatches with a comparably long battery life. At the forefront are watches from Huawei, which also tend to be quite aesthetically pleasing. The GT series in particular has long been able to stay powered for one to two weeks with AOD and all-round tracking enabled. I’ve had the Huawei Watch GT 3 Pro for a few years now. It’s the watch that’s accompanied me day in, day out for the longest time.

Mind you, you don’t necessarily have to go for big brand names. Fellow editor Lorenz recently reviewed the Coros Pace 3, which he found easily lasted two weeks with around-the-clock tracking.

Of course, there are also sports watches from Garmin or hybrid models like those from Withings. I’m excluding them in this overview, however, as they have a different focus.

Why the differences in battery life?

Unfortunately, there’s no conclusive answer as to why Huawei can manage one to two weeks, while Samsung and Apple only manage one to two days. What we can do, though, is rule out hardware differences almost completely. Battery capacity, the display size and resolution, processor and clock frequency are comparable in practically all flagship models from popular brands.

(Note: the Coros watch mentioned above is an exception; it has a much less modern LCD panel with a lower resolution.)

If it’s not the hardware, it then follows that it must be the software.

Practically all Samsung watches rely on Google’s Wear OS. Newer watches from Huawei, on the other hand, come with the company’s proprietary HarmonyOS. Although HarmonyOS is also based on Wear OS, Huawei has adapted it to its own hardware. This is likely the main reason for the differing battery life.

As a developer, you can optimise the performance and endurance of your device much better if you have not only its hardware but also its software under control. Apple usually serves as an example of this, with MacBooks and iPhones performing well.

So why do the Apple Watch and Google Pixel Watch, both loaded with a proprietary operating system, suffer from poor battery life?

What’s really a must-have?

Maybe it’s the features that make a difference after all. For example, the current Huawei Watch GT4 doesn’t offer an ECG monitor or NFC payment. Then again, neither of these functions are in continuous operation anyway, so they shouldn’t really drain the battery. Other common features, such as a heart rate monitor and sleep and sports tracking, are available on Huawei’s watches.

Features and hardware aside, the fact remains that Huawei watches deliver a longer battery life across the board. With no concrete answer, all we can do is speculate. Most likely, Huawei simply has a stricter approach when it comes to battery management. In other words, processes and sensors that aren’t absolutely necessary are stopped more quickly than on Apple, Samsung or Google devices.

The latter three big brands likely leave their sensors in continuous operation, perhaps also using more precise tracking. This can prove significant, especially when it comes to health features and accident detection. In other words, it may come down to your priorities: do you want the full range of features, or are you satisfied with the bare essentials?

As I already mentioned, the only thing I really care about is getting notifications on my watch. And I’m perfectly happy with how Huawei’s watches handle this. To me, all other features are secondary. So much so, in fact, that I’m happy to go without them in exchange for a whopping ten times longer battery life.