OnePlus 13S Review: Compact Flagship Phone Duels Diminutive Competition

The trend of making smaller phones is making a comeback in the Android segment. Focus on Android here, by the way. So far, Samsung's entry-point flagships, like the Galaxy S25, have held the crown of a compact powerhouse, but the competition is getting hotter. After Vivo and Oppo, OnePlus is throwing its hat in the ring. The OnePlus 13s, (which goes by the 13t moniker in China,) wants to reimagine what a small-ish Android phone can offer. 

Technically, it's slightly wider and taller than the iPhone 16 Pro, but lighter than its Apple rival, while its Max variant also costs nearly twice as much. Should you care about it? Only if you like phones that don't hurt your palms. Is it a good phone? Definitely. It's over a hundred dollars cheaper than the Galaxy S25 and iPhone 16 — the world's best-selling phone so far in 2025 — but it offers a handful of perks that outclass its established rivals.

I've spent about a month with the OnePlus 13s (provided by OnePlus for this review) and I think it's a terrific value for its $640 asking price, assuming you can get your hands on it in the US. Go ahead, and groan against market realities like the carrier situation, tariffs, and whatnot. But if you're strongly smitten and thinking about an import, read on to find out whether the OnePlus 13s sounds like your dream compact phone.

The hardware package is the key selling point here, and it's more polished than I expected. You get flat sides, a glass shell with a silky matte surface finish, slim bezels, and a beautiful green shade. The weight distribution is pretty well-balanced, and the in-hand feel is fantastic. Even the camera module is made from a single block of aluminum with an off-color metallic luster. 

On the other hand, a few corners have been cut. The build is IP65-rated, which is not bad. Technically, it's dust-tight and can even handle low-pressure water jets. The competing devices, however, have climbed to the IP68 class, where you get better protection against ingress. Then there's the metallic camera island at the back. It looks and feels sophisticated, but comes with its own ups and downs.

Nadeem Sarwar/SlashGear

First, it won't shatter like the notorious glass-made camera bumps on competing devices — like the iPhone. On the flip side, the polish over the metallic surface gets scratched, and the scars are visible. I scuffed mine alongside the lower side after the phone suffered a quick and short drop to concrete. Thankfully, no bent corners or cracked display came out of it, but the scratched paint lines still hurt my eyes, and heart. The silicon supplied in the retail package is pretty high-quality and I recommend you keep it on.

The 6.32-inch FHD+ (2640 x 1216 pixels) OLED display is pretty sharp and matches the peak 1,600 nits brightness of its flagship sibling. The thin bezels gave the flat panel a clean look, though I have a soft corner for the curved glass on its flagship sibling. As far as the display quality goes, it's acceptable for the price, and the dynamic 1-120Hz refresh rate adjustment is just the cherry on top. 

The only notable issue is the glare, though it's not much of a problem when using the phone outside. The display temperature is on the colder side by default, but it didn't feel nearly as vibrant out of the box.  

Things were fine after I set the color profile to vivid and disabled the adaptive tone feature, which helped achieve a more neutral white look and the colors got an extra dash of saturation. I also enabled the Video Color Boost tool to get some extra visual charm out of hi-res videos. The viewing angles are wide, and there's no apparent color shift visible. 

Users also get the facility to adjust the color temperature and enable a bedtime mode, which can also be visually customized to achieve the most comfortable color temperature and trigger at a set schedule. There's little to complain about the display on the OnePlus 13s, but to get the best out of it, a visit to the display settings page is almost mandatory.

OnePlus has armed its compact phone with a pair of 50-megapixel cameras at the back. Right off the bat, I noticed the color signature and post-processing are quite different compared to the OnePlus 13. The OnePlus 13s' captures fall in the generic category, which is not necessarily bad, but you love to see some character in photos. Daylight shots offer a decent amount of saturation and sharpness, but I highly recommend making a bit of exposure adjustment to compose the frame.

Highlights are handled pretty well, and if you like the color of blue skies as a backdrop, the OnePlus 13s won't give you any trouble with overblown background elements. In general, however, the photos look a tad soft, and some aggressive denoising is usually evident alongside the edges of the frame.

The telephoto camera is the real polarizing element. With steady hands, you can capture crisp long-range shots at up to 4x level, but anything beyond that range starts to show an oil painting effect and butcher the fine highlights. Pictures clicked with the Pro mode turned out better, even though the process is more time-consuming. 

The hi-res mode lets you click 50-megapixel shots, but once again, you need to adjust the exposure to get the right color tone and be patient with the focus lock. The 32-megapixel selfie camera does a decent job, offering quick focus lock and an acceptable color profile in selfies. The 4K 60fps videos are sufficiently stable with ample contrast, and the focus tracking mode does a fine job, too.

The camera output is the most polarizing element of the OnePlus 13s for me, right from the capture experience to seeing the final output. You see, only the main camera is optically stabilized while the telephoto camera is electronically stabilized. The latter actually doubles as a telemacro snapper, but macro mode is only triggered when you switch to the 2x zoom level. 

Main camera sample. (Nadeem Sarwar/SlashGear)

Though it can click some sharp shots with steady hands, due to a lack of optical stabilization, locking the focus is a struggle. If you're trying to capture something fine, such as fiber strands or the fine hair on plant stems, the only successful route is to rest the phone against a still support rather than using it in handheld mode. 

20x zoom sample from the telephoto camera. (Nadeem Sarwar/SlashGear)

The automatic exposure control is usually on point, but the telephoto camera suffers from aggressive overprocessing, even in daylight. Despite being at the "hybrid" 4x zoom level, the algorithmic sharpening gives a painted-over effect to the skin. 

Nadeem Sarwar/SlashGear

In low-light scenarios, noise control leaves a lot to be desired. Capturing moving objects at night is a constant struggle, and there are plenty of blur artifacts due to the focus hunting and subpar stabilization.

2x zoom sample. (Nadeem Sarwar/SlashGear)

At close range, the white balance system acts haphazardly. On the positive side, the OnePlus 13s captures terrific portrait shots. Subject separation is mostly on point, and the details are preserved well. Even indoors, it did a lovely job of showcasing the surface details. The auto-HDR mode isn't the best choice for realistic color reproduction, so I kept it disabled.

OnePlus has crammed Qualcomm's top-of-the-line Snapdragon 8 Elite silicon inside its latest phone, pairing it with 12GB of RAM and up to 512GB of onboard storage. As expected, the performance is top-notch. For heat management, there's a large vapor chamber cooling kit and a graphite layer attached to the rear glass shell. The raw firepower at hand won't disappoint.

I mostly spent my time in "Zenless Zone Zero," one of the most demanding Android games out there. Despite maxing out the graphics settings, I had a lovely time playing the game at 60fps. Even during intense combat, I didn't notice any stutters.

Nadeem Sarwar/SlashGear

I enabled the high-performance mode from within the game booster, but didn't see any noticeable improvement in the raw gameplay. Titles like Call of Duty: Mobile, Asphalt, and Diablo Immortal, as expected, ran without any issues at the highest graphics settings permissible. Editing and exporting videos was quick, and heat management was also admirable.

After running a 20-loop stress test, the OnePlus 13s produced an average stability score of 77%, which is not the best out there, but still a healthy 30% higher result compared to the Samsung Galaxy S25 powered by the same silicon. Interestingly, despite the rising temperature, the performance doesn't fall continuously, and there are some short bursts during sustained loads where the score goes up. Running the ray-traced Solar Bay test, it produced figures in the same league as other phones powered by the Snapdragon 8 Elite and MediaTek Dimensity 9400 SoC.

The unique flavor of Android served by OnePlus, dubbed OxygenOS 15, is arguably one of the most rewarding out there. Of particular mention is the Open Canvas split-screen system (which you'll also find on the OnePlus Pad 3 and other newer OnePlus devices), which lets you conveniently run two apps in portrait mode in a relatively fuss-free fashion. You just have to tap the top or bottom bar to pull an app into the foreground without any resizing hassles involved.

The customizable side panel is one of my favorite elements. You can position it anywhere alongside the vertical edge of the screen, and with an inward swipe, get access to the most frequently used tools, apps, AI utilities, and recent files. On a similar note, the onboard game booster dashboard lets you tap into the high-performance mode, enable 4D vibrations, boost the frame output, record gameplay, and more.

Nadeem Sarwar/SlashGear

There are even dedicated game filters, such as Night Vision, to give you a slight edge. On the connectivity front, we have the O+ Connect system. Think of it as a wireless bridge that lets you transfer files between Apple and OnePlus devices, just like AirDrop. And if you work on a Mac, the app lets you remotely manage files on the OnePlus 13s. The bridge also works on Windows phones.

It's the same app that also lets you remotely access a Mac on the Oppo Find N5 foldable phone. Then there's the Shelf, which is essentially a hub where you can host app shortcuts and widgets, but in a more elegant fashion than vanilla Android or iOS 18.

With OxygenOS 15 on the OnePlus 13s, the signature software of a OnePlus phone is making the big AI leap. My favorite addition is the AI Plus Mind, which essentially serves as a memory bank that captures whatever's on the screen. Just like Windows Recall, the onboard AI jumps into action as soon as you press the new side button. Aside from saving a screen grab, the AI also summarizes the on-screen content and can turn relevant items (such as dates) into one-click action commands, such as adding them to the Calendar.

The biggest advantage of this visual analysis is the reverse search facility. The underlying AI adds what you can broadly describe as alt text to all the snapshots. For example, if you've saved a picture, an important WhatsApp chat about an assignment, or a concert poster, you can directly search for it in the Mind Space using broad terms as "white shirt" or "Travis Scott fest." It's a fantastic alternative for folks, like me, who hoard hundreds of screenshots as a way to save information.

Nadeem Sarwar/SlashGear

Other AI features include a system-wide search system that leverages on-device and cloud-based Gemini Nano models to look for items such as files, notes, and calendar entries using contextual descriptions. In the pre-installed phone app, you can take advantage of real-time call translation and summarization. AI VoiceScribe turns voice notes into transcripts and summaries, somewhat like Apple Intelligence. It also does real-time translation in other apps such as WhatsApp, YouTube, and Zoom in the form of subtitles.

The battery fitted inside the OnePlus 13s is a fairly large 5,850mAh single-cell unit. The company says it's the longest-lasting battery it currently has to offer. It's not remarkably better than the OnePlus 13 based on my regular usage pattern, but it can definitely last a whole day of heavy activity, and then some more.

I can, however, confidently say that it fares noticeably better than the iPhone 16 Pro I use as my secondary device on a daily basis. In my most recent run, as you can see from the image above, the phone lasted a full day and another 20 hours, which is quite impressive because I predominantly used the camera, browsed social media, and played a pretty demanding game.

Nadeem Sarwar/SlashGear

Where it leaves the competition far behind is the charging pace. There's support for 80W wired charging, which can top up the battery from an empty tank to the 75% mark in roughly half an hour. That's over twice as speedy as the phone's direct rivals. Wireless charging, however, is missing. But if it comes as any consolation, the 80W brick comes bundled in the retail package.

There are a few extra goodies in the kit. Bypass charging ensures that the cable doesn't top up the battery, but only keeps the phone running. You can also limit the charging levels to 80%, or enable trickle charging beyond that point. All these measures keep the battery in a healthier state in the long run.

The OnePlus 13s is what I'd describe as "weirdly good." It's not going to wow you at first glance, but it slowly grows on you. You realize the perks of its compact form factor as you spend a few days with it. Similar is the situation with the battery mileage and the speedy 80W charging. The 120Hz OLED screen serves its purpose just fine, even if you're wearing gloves or there are liquid droplets on the screen.

It's a fuss-free performer, thanks to a top-tier silicon. OxygenOS 15, on the other hand, is snappy as usual, with its own set of unique benefits. The Mind Space is one of the most practical AI features I have used so far. For its asking price, the OnePlus 13s surpasses the basics, but not without a few stutters.

Nadeem Sarwar/SlashGear

The camera hardware is powerful, but it could use some tuning to really shine. The lack of wireless charging will be missed, while the ingress protection could've been better. With the OnePlus 13s, you are essentially picking what matters to you and then choosing to live with its flaws.

The biggest challenge would be getting your hands on one. So far, plans of a US launch are still under wraps. As far as the alternatives go, the iPhone 16e is the best bet, though it makes some serious cuts compared to the OnePlus 13s. The situation with the Samsung Galaxy S24 FE or the Google Pixel 8a is not too different. Pound for pound, however, the OnePlus 13s emerges on top.