As OnePlus has just announced its latest Android, we’re keen to see how it compares to Samsung’s current flagship.
We’ve reflected upon our time with the OnePlus 15 to the Samsung Galaxy S25 Ultra and compared our experiences with the below.
Keep reading to learn more about the flagship smartphones and decide which will likely suit you best.
Price and Availability
The OnePlus 15 is available now with a starting RRP of £849.
Although the Samsung Galaxy S25 Ultra has an official starting RRP of £1249/$1299, as it’s nearly a year old it’s possible to nab the handset with a solid discount. For example, at the time of writing you can pick up the phone for £999 from Amazon.
Design
- Both share a rounded corner and flat edged design
- OnePlus 15 has IP68, IP69 and IP69K ratings
- Galaxy S25 Ultra comes with an S Pen stylus
While OnePlus phones used to sport a unique curved design, the OnePlus 15 looks remarkably similar to a lot of its competitors, including the Samsung Galaxy S25 Ultra. Both phones have the same rounded corners and flat edges, which means they’re hard to differentiate in a crowd.
OnePlus 15
Samsung Galaxy S25 Ultra
Having said that, the OnePlus 15 does come in a choice of more interesting colours, including Sandstorm which is the first of its kind to use the micro arc oxidation process, so the surface stays cool and is actually tougher than both aluminium and even titanium too.
Speaking of durability, the OnePlus 15 is fitted with not one but three IP ratings, including IP68, IP69 and even IP69K which means it can withstand both submission in water and even hot-water jets. In comparison, the Galaxy S25 Ultra is fitted with just an IP68 rating but in reality this is probably all you really need from a handset.
Finally, the OnePlus 15 also sports the new Plus Key which is OnePlus’ answer to Apple’s Action button and works as a shortcut to different apps and functions. It’s a useful tool, however it does come at the cost of the ringer switch.
Winner: OnePlus 15
Screen
- Samsung Galaxy S25 Ultra has a larger display at 6.9-inches
- OnePlus 15 offers a 165Hz refresh rate, making gaming feel impressively smooth
- S25 Ultra has an anti-reflective coating
Although both handsets share a similar design, they have different screen sizes. While the OnePlus 15 makes do with a 6.76-inch panel, the S25 Ultra instead is fitted with a 6.9-inch display. Both, however, are AMOLED panels and other impressively thin bezels too, for an immersive viewing experience.
While both boast their fair share of premium screen technologies, the OnePlus 15 undoubtedly takes the edge. For example, although the S25 Ultra has a fairly standard 120Hz refresh rate, the OnePlus 15 boasts a slick 165Hz refresh rate alongside a rapid 3200Hz touch response rate. That means gaming feels especially responsive, but we’ll get into that more later.
However, one area where the S25 Ultra excels is with its anti-reflective coating that reduces reflections both indoor and outdoors. This, unfortunately, is missing from the OnePlus 15 but the phone is still perfectly usable without it.
Winner: OnePlus 15
Camera
- Samsung Galaxy S25 Ultra has four rear cameras
- OnePlus no longer partners with Hasselblad for the 15, and instead uses OnePlus’ own DetailMax algorithm for image processing
- OnePlus 15 offers 4K@120fps filming, which is an Android first
Considering the S25 Ultra has a top spot on our best camera phones list, the OnePlus 15 has a lot to live up to. Before we look into the differences between the phones, we’ll see what really makes the S25 Ultra one of the best for photography.
With a 200MP main, 50MP ultrawide, 10MP 3x and 50MP 5x lenses, the S25 Ultra is a confident snapper that can take solid shots even in low lighting conditions. Of course, the main 200MP lens performs the best, and is the lens you’ll use the most, and captures plenty of light and detail with minimal blowout.
One quirk of Samsung’s cameras is they tend to make images look overly vibrantly and less true-to-life. While they look great for social media, this can be a bit of a love-hate situation.
While the OnePlus 15 shares a similar camera setup to the OnePlus 13, with 50MP main, 50MP periscope and 50MP ultra lenses, it’s no longer in collaboration with Hasselblad and instead uses OnePlus’ own DetailMax algorithm for image processing.
Alongside DetailMax, there are some other key differences with the OnePlus 15, including the sensor sizes. In fact, the 50MP main lens’ sensor is now the same size as the mighty iPhone 17 Pro Max at 1/1.56-inches. This larger sensor results in images that are brilliantly detailed, regardless of the shooting conditions.
In addition, the OnePlus 15’s periscope telephoto offers a larger 1/2.75-inch sensor and enhanced 7x in-sensor zoom, which we found does a “much better job” than the likes of the Google Pixel 10 too.
Finally, content creators will especially be tempted by the OnePlus 15 as it’s the first Android to offer 4K@120fps with Dolby Vision. In comparison, the S25 Ultra caps out at 8K@30fps.
Winner: OnePlus 15
Performance
- Snapdragon 8 Elite Gen 5 vs Snapdragon 8 Elite for Galaxy
- OnePlus worked with mobile game developers for a better gaming experience
- Bypass charging is available on the OnePlus 15 and S25 Ultra
The OnePlus 15 is one of the first phones to ship with Qualcomm’s latest flagship processor, Snapdragon 8 Elite Gen 5 which, as expected, churns out impressive benchmarking scores.
In reality, those scores translate to seriously fast animations where everything feels instantaneous and minimal lag detected. Plus, as we touched upon earlier, the OnePlus 15 is a fantastic gaming companion.
OnePlus worked with mobile game developers to enable its 165Hz refresh rate across popular games, including Clash of Clans, Brawl Stars and Call of Duty Mobile. Not only can the OnePlus 15 deliver a full 165fps experience, but the phone rarely heated up during use either.
On the other hand, the Galaxy S25 Ultra runs on a custom version of Qualcomm’s 2025 flagship processor, Snapdragon 8 Elite for Galaxy. Much like the OnePlus 15, the S25 Ultra feels fast and responsive in everyday use, including when gaming. While we did notice the phone would warm up during longer periods of gameplay, it still made for a solid experience.
Winner: OnePlus 15
Software
- OnePlus’ OxygenOS is one of our favourite Android skins
- Galaxy AI remains ever-present in the S25 Ultra
- Samsung promises a more generous promise of Android and security updates
OxygenOS, OnePlus’ Android skin, is one of our favourites, as it’s easy to use and highly customisable too. There’s also plenty of new additions in OxygenOS 16 such as Plus Mind that stores and uses AI to organise screenshots and voice notes, much like Nothing’s Essential Space.
In addition, some existing AI features have seen updates too such as AI Scan which can now capture presentation slides and remove shadows from the image.
OneUI, Samsung’s skin, is equally intuitive too and has the Galaxy AI built-in which allows you to combine multiple app actions into a single request. Included with the Galaxy AI toolkit are features such as Now Brief and, of course, Samsung’s brilliant photo editing suite too.
Finally, while the S25 Ultra is promised to see seven OS upgrades, which is one of the longest promises of any phone, the OnePlus 15 is only promised four.
Winner: OnePlus 15
Battery
- OnePlus 15 has a much larger battery at 7300mAh
- Samsung optimised the charging process with the S25 Ultra, but it still caps at 45W
- Both support wireless charging, but the OnePlus 15 boasts up to 50W
The difference between the OnePlus 15 and S25 Ultra’s batteries is vast to say the least. While the S25 Ultra is fitted with a 5000mAh cell, which ends the day with around 20-30% charge remaining after up to four hours of screen time, the OnePlus 15 boasts a mammoth 7300mAh capacity.
Even so, it’s worth noting that the OnePlus 15 isn’t quite a two-day handset, as we would end days with five hours of screen time with a maximum of 40% battery. However, as the OnePlus 15 supports 120W SuperVOOC charging, which is among the fastest around, topping up isn’t exactly an issue.
In comparison, although Samsung did optimise its charging process so the S25 Ultra charges faster than its predecessor, it still caps at 45W . That translates to taking around an hour to reach 100%.
Otherwise, both handsets support wireless charging too which is always a useful addition. While the S25 Ultra supports a fairly standard 15W, the OnePlus 15 benefits from up to 50W when paired with a compatible AirVOOC charger (which, of course, is sold separately).
Winner: OnePlus 15
Verdict
It’s fair to say that when looking at the OnePlus 15 and Samsung Galaxy S25 Ultra side-by-side, the latter feels somewhat outdated in comparison. While the S25 Ultra remains a solid Android and a brilliant all-rounder, the OnePlus 15 offers that bit more.
With Snapdragon 8 Elite Gen 5, Android-first camera features and a mammoth 7300mAh, the OnePlus 15 is a more appealing choice for those who want powerful performance and something different from their phone.
