Samsung was one of the pioneers of the slim flagship smartphone concept, releasing the Galaxy Alpha model in September 2014. It was a device with a body thickness of only 6.7 mm, aimed at a young audience and buyers who valued design. Does this remind you of anything? Indeed, 11 years later, history has almost repeated itself. In 2025, Samsung released the Galaxy S25 Edge flagship smartphone, which also tries to stand out from other models in the S25 line with an extremely thin body 5.8 mm thick. Looking ahead, I will note that the Galaxy Alpha did not receive a sequel at the time – buyers did not appreciate the thin body, which resulted in less autonomy (the battery was only 1860 mAh). Perhaps the same fate awaits the Galaxy S25 Edge: there are already rumors that there will be no more slim models in the S26 line. However, unlike the Galaxy Alpha, which had significant compromises (a weaker processor and screen compared to the flagships of the time), the S25 Edge actually has quite powerful specifications. So I decided to use the smartphone for a while to see if it's possible to live with two cameras, if the battery life is really that bad, and if there is a future for ultra-thin flagships.
How a thinner body changes the perception of a smartphone with a fairly large screen
The first thing you notice when you pick up the Galaxy S25 Edge is its size and weight. The smartphone is only 5.8 mm thick, which is 1.5 mm less than the “regular” Galaxy S25+. Visually, it's about the size of a stack of seven credit cards – something that's hard to imagine for a modern 6.7-inch smartphone. The device is also relatively light, weighing only 163 grams, which is even less than some compact models. In real life, this “diet” makes itself felt, as the smartphone feels very thin and light. The Galaxy S25 Edge has a kind of wow effect: when you pick up the device, it feels like you're holding only the screen for a while.
Photos don't convey this effect, but after just a few days of use, regular smartphones start to seem too thick and heavy. The Galaxy S25 Edge is really easier to carry in different pockets, and it's much more comfortable to hold it in one hand for a long time. At the same time, the build quality has not suffered, thanks to the titanium frame and durable glass (the front uses the new Gorilla Glass Ceramic 2, the back uses Gorilla Glass Victus 2), the device feels solid.
Concerns that such a thin design might bend or be fragile proved unfounded: the smartphone proved to be reliable and even withstood blogger JerryRigEverything's rigorous bend test without damage. The Galaxy S25 Edge does not feel fragile in your hands; on the contrary, it is a full-fledged flagship with IP68 protection, so reliability has not been sacrificed for the sake of a thin body.
The reduction in thickness is particularly interesting given the smartphone's large 6.7-inch screen. The Galaxy S25 Edge is equipped with the same display as the S25+: Dynamic AMOLED 2X with QHD+ resolution (3120×1440), HDR10+ support, and a dynamic refresh rate of 1–120 Hz. The screen has excellent color reproduction and is very bright (peak brightness up to 2600 nits). The image looks extremely clear with a density of over 500 ppi, so even small text is comfortable to read. The smoothness of the interface is also top-notch thanks to 120 Hz.
The fingerprint scanner is built into the display and works very quickly. In fact, there are no simplifications to the screen due to the thin body – we have Samsung's flagship display in all its glory.
The display bezels are as thin as those on the S25+, but the corners of the body are slightly less rounded, bringing the design a little closer to the Ultra model. But overall, the only thing that affects the usability of the large screen is the shape of the device itself: the S25 Edge is still wide and tall, so not everyone will find it comfortable to reach the top of the screen. Another point is that if you put on a regular silicone case, the wow effect of the thickness is largely lost, so if you are confident that the smartphone will not fall, it is most pleasant to use it without a case.
Despite its smaller thickness, the Galaxy S25 Edge, as befits a flagship, has stereo speakers with Dolby Atmos support. They provide quite loud sound, but you can't fool physics. Due to the thinner body, the internal volume for the speaker resonance chambers is smaller, so there are fewer low frequencies and the maximum volume is slightly lower than in thicker models such as the S25 Ultra. The sound is a little “flatter,” although still good quality. However, overall, the volume and quality of the speakers were more than enough for me to watch videos on YouTube and make video calls.
Does a slim smartphone need a flagship processor?
One of the key questions is whether it makes sense to install a powerful processor in such an ultra-thin device. Samsung decided that it does. That's why the Galaxy S25 Edge is equipped with the top-of-the-line Qualcomm Snapdragon 8 Elite for Galaxy chipset, 12 GB of RAM, and 256 or 512 GB of internal storage. In essence, the Edge has the same “brains” as the top-of-the-line S25 Ultra, so in terms of speed, it is almost on par with other flagships.
Why almost? The thickness of the case imposes its own limitations in terms of heating, which in turn forces the system to maintain lower frequencies under long-term load. So, if we take purely synthetic tests, neither Geekbench 6 nor PCMark 10 show any significant lag behind the Galaxy S25 Ultra.
However, the 3DMark Wild Life Extreme stress test, which puts a longer load on the processor and graphics, shows a greater loss of performance due to the heating of the case. Although the S25 Edge has an evaporative chamber cooling system, it is significantly smaller in area than the S25 Ultra. As a result, under prolonged load, the smartphone heats up faster and reduces the processor frequency more to avoid overheating.
This approach does not mean that the Galaxy S25 Edge has poor performance or overheats all the time. The Snapdragon 8 Elite still handles any Android app with ease, and the cooling system, coupled with frequency reduction, is sufficient to keep the body only slightly warm in most tasks. In particular, the device can record 8K video for over 10 minutes without any problems and only becomes slightly warm. However, it can be said that the Galaxy S25 Edge is designed for normal use, and if you need long gaming sessions or DeX mode, a “thicker” smartphone, such as the S25 Ultra, is more suitable for better cooling and performance.
Since Samsung used a top-of-the-line chip, other flagship features are still there: the S25 Edge supports wireless charging (15W) and reverse charging, and has UWB, NFC, Wi-Fi 7, and Bluetooth 5.4. So, in terms of hardware, the S25 Edge is a true flagship without any significant simplifications, unlike the Galaxy Alpha in 2014, which had a simplified processor.
However, in my opinion, a slim smartphone does not need the most powerful chip, because it is difficult to use it to its full potential due to thermal limitations. Samsung could have used the Snapdragon 8s Gen 4 or Snapdragon 7s Gen 3 processors, which are inferior in performance to the Snapdragon 8 Elite, but still have fairly high performance. However, Samsung's logic is understandable, as the flagship processor is built using a more advanced 3nm process, has a smaller thermal package, and even when frequencies are “suppressed,” it delivers higher performance than simpler solutions. However, the use of Snapdragon 8s Gen 4 or 7s Gen 3, even without other simplifications, would allow the Galaxy S25 Edge to better compete with other models in the S25 line thanks to its more moderate price.
Two cameras for all occasions
Another controversial aspect of slim smartphones is the reduced number of cameras. In particular, to save space in the Galaxy S25 Edge, the manufacturer sacrificed the telephoto lens, leaving two cameras on the rear panel: a 200-megapixel wide-angle camera (the same sensor found in the S25 Ultra) and a 12-megapixel ultra-wide-angle camera with a 120° viewing angle and autofocus (meaning it can also be used for macro photography). The front camera is a 12-megapixel module with Dual Pixel autofocus, the same as in the entire S25 line. On paper, this “minimum” is sufficient for most everyday scenarios. But isn't the lack of a third telephoto lens noticeable?
First, let's talk about the image quality of the available cameras. The main 200-megapixel camera performs on par with the S25 Ultra, as expected. In daylight conditions, photos are detailed, with the brand's signature “vibrant” color reproduction. At night, the detail drops, but you can still get high-quality shots.
Even without an additional lens, this sensor allows you to zoom in by cropping the image. In essence, the central part of the matrix is used, which is equivalent to a 2x optical zoom. And I must say, 2x looks pretty good. Moreover, with digital magnification up to 3-5x (depending on conditions), the difference with a separate telephoto lens is not very critical, because the S25 Edge can extract decent detail at medium zoom levels. Of course, we are talking about daylight; at night or in difficult conditions, digital zoom is not as effective.
The 12-megapixel ultra-wide-angle lens is a typical Samsung sensor that we have seen in other models. It takes good landscape shots, with colors matching the main camera during the day and sufficient sharpness.
The front camera is also impressive. The 12-megapixel module with autofocus takes clear selfies with correct exposure in good lighting conditions, and it is also sufficient for video calls and social media.
I can't say that I really missed having a telephoto lens when using the Galaxy S25 Edge. As I mentioned, the crop from the main camera gives a decent 2x zoom, and you don't often need to shoot with zoom in everyday life. However, if you need a smartphone for subject photography, for example, for photographing goods for SMM, then a digital 2x zoom will not be enough. And when traveling, optical zoom will still allow you to take more interesting photos. However, in general, the two cameras of the S25 Edge cover, perhaps, 90% of the everyday needs of the average user.
Poor battery life?
It's time to discuss the most controversial aspect of thin smartphones – battery life. Due to its slim design, the Galaxy S25 Edge has a 3900 mAh battery, which is even less than the base Galaxy S25 (4000 mAh). For comparison, the thicker S25 Ultra has a 5000 mAh battery. Obviously, capacity has fallen victim to design, and many feared that the Edge would drain record fast. Were these fears justified? It depends on who you ask.
A somewhat confusing answer, but users who don't let go of their smartphones all day and drain even the S25 Ultra in a day will definitely be disappointed with the Galaxy S25 Edge's battery life. For me, it came as no surprise; I was prepared for the fact that the smartphone would not be able to provide long-term operation, but it still surprised me.
On average, I took it off the charger at 8 a.m., and after a day of fairly active use with the screen on for 5 hours until 10 p.m., I still had almost 30% battery life left. The smartphone could discharge faster when, for example, I went for a walk in the park and took about 50 photos, or spent 30-40 minutes on a video call in Google Meet. On such days, the number of hours of active screen time could be less — 4 or 4.5 — but by 10 p.m., the battery charge still remained at 20%. Considering that I could recharge the phone in the car when I was driving somewhere on business, and that I could recharge it at home or in the office even during power outages, I generally did not experience any discomfort due to the Galaxy S25 Edge's battery life. The device can provide a typical day's use. However, if you put the S25 Edge under more serious load, for example, playing games for several hours, it will definitely run out of power before the end of the day, and you will remember Samsung's engineers with a kind word.
Therefore, the battery life of the Galaxy S25 Edge greatly depends on the user's needs. If you have an active day and are far from a power outlet, you can immediately turn on power saving mode, which will reduce background processes and lower the screen refresh rate. After all, in normal use, the Galaxy S25 Edge will definitely not last such a day.
Fortunately, Samsung has made sure that charging is as hassle-free as possible. The Galaxy S25 Edge supports 25W fast wired charging (Power Delivery standard) and 15W wireless charging. There is no charger included, but with a 25W USB-C adapter, I was able to get ~50% charge in 25-30 minutes, and a full charge takes about 80 minutes. It's not a record, but it's fine overall.
Overall, I wouldn't call the S25 Edge's battery life a complete failure, as it generally lasts until the end of the day with normal use. But compared to the S25+ and S25 Ultra, the battery life here is nothing to write home about. In this respect, the story of the Galaxy Alpha has repeated itself somewhat: you have to choose between a thin and light body or ample battery life. And, of course, in today's world, most people will choose longer battery life. However, I think that if more people could try the S25 Edge in their own usage scenario, they would realize that a 3900 mAh battery is not that small.
In conclusion
Well, I would call the Galaxy S25 Edge a bold experiment by Samsung and an attempt to add new sensations to the design of monoblock smartphones, which has become somewhat monotonous in recent years. The Edge demonstrates that a modern smartphone can be slim and offer most of the features found in flagship models. After all, it has a great screen, good performance, an excellent main camera, and all the flagship features in place. Using the Galaxy S25 Edge reminded me of the S10+, probably Samsung's last truly comfortable flagship in terms of weight and size. For a certain category of users who have long dreamed of bringing back that feeling, the S25 Edge may be the perfect solution.
So, is the Galaxy S25 Edge “the most underrated smartphone of 2025”? To a certain extent, yes. It deserves more attention than it has received, as it offers a rather unique user experience. When you hold this smartphone without a case, you really understand how overloaded modern flagships have become. So, if you want good specs in a relatively thin and light body and don't care too much about battery life, then the S25 Edge will work for you. If not, then no. You either love this smartphone or you hate it; there's probably no third option.