One Week on a Charge: The OnePlus Watch Lite Review

The OnePlus Watch Lite serves as the brand's new entry-level option, designed for users exploring wearables and fitness tracking for the first time. Notably, OnePlus chose to move away from Wear OS for this device, yet it retains the familiar OnePlus Watch aesthetic.

Design

The watch features a large, clear 1.46-inch AMOLED screen, easily visible even in bright conditions. This display boasts a 464 x 464 resolution (317 PPI). While the default maximum brightness is 600 nits—sufficient for daily use—it can peak up to 3000 nits when utilizing the integrated OnePlus fitness applications.

Its design includes a functional rotating crown and a smaller secondary button, mirroring the Watch 3. The Watch Lite is exceptionally thin—the slimmest OnePlus has ever produced—making it light and comfortable for continuous wear. A minor caution, common among smartwatches, is that wearing it too tightly may cause the crown to press against the wrist.

The screen is protected by "Sapphire like glass," which demonstrated good scratch resistance. The watch is also durable, carrying a 5 ATM water resistance rating and passing IP68 testing. It is equipped with a full suite of expected health sensors.

Hardware and Performance

Despite housing a relatively small 330 mAh battery compared to other OnePlus offerings, the optimized software platform provides substantial longevity. In testing, using all features, including automated fitness and sleep tracking, with the display set to turn off after 10 seconds of inactivity, the watch reliably lasted a full week between charges. While a Battery saving mode is available for extended life, it was never necessary.

Recharging is quick: a full charge takes 90 minutes, or a 10-minute boost provides an additional 24 hours of use. Both charging metrics were verified.

Powering the device is a BES2800BP processor, paired with 4GB of storage. While this is not intended for storing massive media libraries, the memory and storage capacity ensure the operating system runs smoothly and quickly. The watch supports Wi-Fi and Bluetooth, but an LTE version is not available.

Unique Connectivity

A standout feature is the watch's dual connection capability. It can be simultaneously paired with two smartphones—either two Android devices or one Android and one iPhone. This feature is particularly unique at this price point; the only other watch known to offer it is the much more expensive Tag Heuer E5 Connected (priced over £1,000).

Sensor Array

The watch includes a comprehensive array of sensors for fitness and health data collection: Accelerometer, Gyroscope sensor, Geomagnetic sensor, Air pressure sensor, Optical heart rate sensor, Optical blood oxygen sensor, Wrist temperature sensor, and Ambient light sensor. This robust collection allows for detailed fitness data reading and metric conversion.

Specs

Specification	Details
Design	Silver steel, Black steel, or Bezel
Case	Silver stainless steel or Black stainless steel
Strap	White fluororubber with stainless steel buckle or Black fluororubber with stainless steel buckle
Wrist size	140-210 mm
Bottom case	Plastic (PA+55%GF) with glass sensor area
Size	44.98 mm (excluding lugs) x 44.98 mm x 8.9 mm (excluding optical health sensor area)
Weight	Approx. 35 g (excluding wrist strap), 59 g (including wrist strap)
Screen	1.46-inch AMOLED, 464 x 464 pixels
Brightness	Default max. brightness: 600 nits, High brightness mode: 1500 nits, Peak brightness: Up to 3000 nits (only in self-developed workout mode, which will automatically turn on in strong sunlight)
Cover glass	2.5D Sapphire crystal
PPI	317
Battery capacity	339 mAh (typical), 330 mAh (rated)
Battery life	330 mAh (rated capacity) (confirm the sports mode information)
Maximum battery life	10 days (based on battery life model test results)
Typical battery life	7 days
Always-On Display (AOD) battery life	4 days
Charging time	0% to 80% in 60 minutes or less, Full charge in 90 minutes or less
Fast charging	10-minute charge for 24 hours using MCU BES2800BP
Operating system	OxygenOS Watch 7.1
Storage	4GB EMMC
Bluetooth	Bluetooth 5.2, Classical Bluetooth, BLE, Profile, HID, HFP v1.6, HSP v1.2, A2DP v1.2, AVRCP v1.5, SPP v1.1 and later versions
GPS	Dual-band L1+L5, including Beidou, GPS, Galileo, GLONASS, and QZSS
Calling	Bluetooth calling
Compatible smartphones	Android 9.0 or iOS 14.0 and above
Sensors	Accelerometer, Gyroscope, Geomagnetic, Air pressure, Optical heart rate, Optical blood oxygen, Wrist temperature, Ambient light
NFC	Supported, but mobile payment is not supported
Other features	Intelligent connectivity cross-OS dual-phone pairing, Over 400 watch faces, Health 60s Wellness Overview, Mind and Body Evaluation, Sleep tracking (deep sleep, light sleep, REM sleep, awake time, respiratory rate, sleep SpO2), Sleep score and suggestions, Sleep mode, High/low heart rate alerts, Resting heart rate, Sleep benchmark heart rate, Daily activity and achievement reminders, Blood oxygen monitoring (manual SpO2 measurement, all-day tracking, low SpO2 alerts), Breathing exercise, Fall detection, Cycle tracking, Wrist temperature, Over 100 sports modes
Durability	5ATM, IP68
Package contents	One watch (strap included), Integrated watch charging cable, User guide, Safety and warranty booklet

 

Software

The watch runs a customised version of software for its os called Real Time OS, but it is worth diving into what this actually is. 

Think of it this way: the RTOS is the watch's brain, but it's a super-focused brain that’s built for one thing—speed you can trust.

Here’s the simple breakdown:

Guaranteed Speed: It's all about making promises. An RTOS guarantees that super-important stuff, like checking your heart rate, will happen exactly when it's supposed to. If a notification pops up, the watch can't be late buzzing your wrist. This is why your health data is accurate and the watch feels instantly responsive.

The Battery Boss: Full operating systems, like the one on your phone, are resource hogs—they drain the battery by running tons of stuff in the background. An RTOS is tiny and ultra-efficient. It only runs what's absolutely necessary, which is the main reason why a watch like the one in your document can last a full week between charges. They sacrificed a bigger, full-featured OS (like Wear OS) for that killer battery life.

Laser Focus: The RTOS is always prioritizing. If you’re tracking a run (top priority) and a weather app wants to update (low priority), the OS immediately pauses the weather check to make sure the run tracking stays flawless. This focused approach is key to why the watch feels fast and smooth.

Basically, an RTOS lets smartwatches be smart and still have amazing battery life, because it only does what it absolutely has to, and it does it right on time.

That is all well and good but what is it like to actually use this RTOS in the real world. Well in essence imagine using any other smartwatch but in battery saving mode as that is essentially what you're doing. It does not as previously mentioned support any additional applications that can be sourced from the like of the Wear OS app store as there are no apps available. This can be a blessing as mentioned above but it also comes with problems. The biggest issue I had with the watch is that I was not able to get my weather app to work with location which made this aspect of the watch completely redundant. (This was raised to OnePlus as a concern but I still don't have a resolution as it only seems to be the weather App that is affected)

I also found that the notification support was lacking to the point where I could not reliably use it for notifying me of events such as email or messaging. Whilst it would show you the notification and you could view some of them you could not do any further to that as it would prompt you to open it on your phone. One of the main features I use a smart watch for is the triage of messages and emails during my day and the OnePlus Watch Lite was not great in this respect. 

On the flip side I did find that it was very good at tracking my steps and sleep cycles aided by the fact that I could wear the watch when sleeping without really noticing it was still on. The automatic exercise tracking that is built into the watch workout modes is great and it picked up when I had been walking for a prolonged period of time with no issue. I also really like the overview of the workout that you get when you have completed your walk/run/cycle within the OHealth app on your connected phone.

I actually like this feature so much that I have now bought a OnePlus Watch 3!

 

I found that the quality of the speaker for calls was also pretty good and I was able to be both heard and hear clearly when I got calls on the watch when I was out and about. This is particularly useful when I am driving my work van as I have to have my work phone hooked up to the van's infotainment so my personal phone would normally be on speaker phone. Being able to prompt the watch to make calls and receive them from a long press on the watch's crown button was very handy.

As you can see below you have options to have your apps in either a grid style view or a list view. I preferred the later as it felt more organized to me.

You also have the ability to use tiles for your frequently used tasks and there is a new widget style page when you wipe left from the watch face which allows you to have your frequently used apps to be accessed quickly

Fitness tracking

So how is the watch for tracking health and fitness? Well I am going to be totally honest here the vast majority of the time I have been wearing the watch I have been working on which involves long durations of me sitting and driving so I have not been able to get the best out of the watch for health tracking purposes.

It does have a rather handy 60s health overview which combines an ECG and other metrics to give you a snapshot of your health for that time period. I maybe only used this option once to try it but it is there if it is something that you want to know more about. As with all EKG's on smartwatches this is an approximation not a 100% accurate assessment if you are concerned about your health or the results produced on your watch always seek advice from a qualified physician.

What I have seen though is that the sleep tracking is pretty good and accurate as is the step count and heart rate. When I have been able to go for walks of any significance the watch has been able to pick this up easily and the traced route is fairly accurate. That is about as much as i can say regarding the health and fitness aspects from my own experience.

I can see that this however would be very useful for someone who is of a sportier ilk and wants the basics kept track of. It is never going to give you an athlete grade of metrics that you could get from a dedicated running watch like that of the Garmin Forerunner range but it is not designed for that. The exercise modes are well supported with all your usual exercises accounted for but it also has some more obscure options such as Badminton and Outdoor Ski/Snowboard for those of you who indulge in those activities. I would have liked to have tried the Outdoor cycle tracking option whilst Mountain biking but it being January I have not ventured out on the bike so far this year!

Conclusion

If you are looking to get a fitness focused wearable for this year's fitness journey and are not wanting to be burdened by the subscriptions required by the likes of Fitbit etc then the OnePlus Watch Lite is worth a look. The fact that this can be used on both iOS and Android is a welcome though not unique (at this price point it may be) addition. If on the other hand you need a smart watch to be a bit more smart then this may not be the device for you as the ability to add third party apps may be the limiting factor that breaks the allure for you.

Whilst the Oneplus Watch Lite is not the watch for me I was impressed enough by its charm and performance that I have now bought the OnePlus Watch 3 which offers many of the same benefits without the shortcomings albeit I have to charge  it more frequently!

You can pick up the OnePlus Watch Lite from the OnePus website now and it is currently on offer for £159.00 (standard RRP £179.00.