The Xiaomi 15 Ultra is here to take on the likes of Samsung and Apple and while like many 2025 flagship phones, it’s an iterative edition, there are some key upgrades to be aware of, as well as one downgrade.
A big new camera
As you probably already know, the Xiaomi 15 Ultra is a camera-focused phone and it’s unsurprising that the firm has kept things relatively similar to the amazing 14 Ultra in this department.
You still get four rear cameras but a new 200Mp periscope lens makes its debut, replacing the 50Mp of the 14 Ultra.
Although the zoom length has been reduced from 5x to 4.3x, the camera has all that extra resolution as well as some other spec upgrades which result in 136% more light capture, according to Xiaomi.
It it worth noting briefly on the camera front that the main camera no longer has a variable aperture, which is a shame.
A big performance jump
While it means the 15 Ultra matches many rivals from other phone makers, the Snapdragon 8 Elite has proven to be a big step up in mobile chipset prowess.
Not only is the chip a lot more powerful than the 8 Gen 3 found in its predecessor, but it’s also much more power efficient too.
In our usual benchmarks, the 15 Ultra scored 42% better in Geekbench 6, which is a huge increase and no less than four hours and 35 minutes longer in the PCMark battery test – that’s 37%!
Chris Martin / Foundry
Bigger battery, same space
Something Xiaomi has managed to do is increase the battery capacity without increasing the size of the phone itself (though as a side note, the Silver Chrome model is a tiny bit bigger than white or black).
This, like the OnePlus 13, is achieved by using 10% silicone carbide technology so the battery has gone from 5000- to 5410mAh.
However, it’s a shame we don’t get the 6000mAh cell found in the Chinese version.
As mentioned above, the Snapdragon 8 Elite is very power efficient, so these two combined results in much stronger battery life.
A design backstep
This one is more subjective but the design of the 15 Ultra, while similar, has taken a step back. The rear cover no longer has a vegan leather finish which I particularly liked. It looked great and was really grippy.
This year, as you can see, Xiaomi has changed it to a glass fibre composition and my black sample is a little too glittery for my liking but more importantly, it’s really slippery.
I imagine the same is true of the white model, which also has an effect not to my taste. The slight saving grace here is the new Silver Chrome colourway which does have the vegan leather.
Chris Martin / Foundry
However, multiple peers testing that model report that the glass fibre section feels plasticky. If you’re getting the Photography Kit for the 15 Ultra then this has a vegan leather finish as opposed to the woven fabric of the previous model.
