My personal thoughts. - They trade blows, neither one is always the best.
Now I should preface by saying that both sensors did far better than I expected them to. A lot of these images don't look very dark, but when I was actually taking them, sometimes I could barely even see what I was taking photo's of, especially the one's of the car exteriors and interiors. Both sensors brighten dark environments up considerably, more so than any other camera phone I've previously used.
Essentially, the truth is there is very little between these two sensors, and both perform very well. Unless you're really pixel peeping, often times it's hard to see differences in either one's favour. They trade blows shot to shot, as you will see from the following examples. In some shots the Britecell does better, in other shots the IMX260. Other times the one that ends up better is more of a case of which part of the photo you're looking at, and therein lies some of the differences that I did notice.
What are the differences? - The shot that is the notably larger file size is usually always the one with more detail.
As stated above, these sensors trade blows, sometimes one performs better, other times the other. I'm not actually sure how much of that is down to the sensor, and how much is down to the software or processing, as one alarming trend I've noticed is that every single shot that I prefer out of the two, is usually always the one with the much larger file size. If one photo of the two is larger in file size by a noteworthy amount, it's almost a foregone conclusion that it will be the more detailed, sharp and/or less noisy than the other.
How about differences beyond those dictated by image file size?
Neither one is consistently the better performer with respect to detail and noise, but I would say the IMX260 is ever so slightly more reliable with these two things. Again, I don't know if that's actually to do with the sensor, or to do with the software.
Another difference I've noticed is that background objects, e.g. those further behind your main object of focus, can sometimes be less in focus with the Britecell than they are in the IMX260 shots. It's almost like the Britecell now and again chooses to have a narrower focus range, which in shots looks as if it's using more depth of field or a higher aperture, though a quick look at EXIF data shows it's actually using the same aperture and settings as the IMX260. Conversely, the Britecell also now and again has up close or foreground objects, notably those closest to the camera user, even if they're closer than the thing you're focused on, looking more in focus than they do with the IMX260. This weird difference occurred several times during my comparison, and I thought it odd.
Another difference I noticed is that on occasion, in very low light conditions, the Britecell sometimes pushed red in terms of white balance, whilst the IMX260 pushed more on the yellow side. Not really sure which is more accurate, I'd imagine something in-between. But most of the time the two are very similar in overall colour tone and balance.
Lastly, in extreme low light conditions, I found the IMX260 focused faster than the Britecell. Where the IMX260 focused reliably and efficiently, the Britecell would seek for just a split second or two before it took the shot. Neither ever actually failed to focus however, it's just that sometimes the Britecell took a little longer. In daylight or ordinary low light conditions, both focus ridiculously fast.
Anyway, on to some of the comparison shots. I've posted the shots in full, as well as links to crops of different parts of each shot, so you can get a close up of all aspects of the images, without zooming in yourself. For most shots I have links showing an up close crop of the right side, left side, top and bottom of each image.
Top is Samsung's Britetcell, bottom is the Sony IMX260.
1. Britecell - 3.8mb, IMX260 - 3.7mb.
Winner: Very close, Britecell more detailed in areas, Sony in others.
Comparison 1 - Right
Comparison 1 - Left
Comparison 1 - Top
2. Britecell - 3.2mb, IMX260 - 3.1mb.
Winner: Also very, very close, Britecell a fraction more detailed in areas, Sony in others.
Comparison 2 - Right
Comparison 2 - Top
3. Britecell - 3.9mb, IMX260 - 3.6mb.
Winner: Britecell easily takes this one. Just a lot more detail and sharpness overall.
Comparison 3 - Right
Comparison 3 - Left
Comparison 3 - Top
4. Britecell - 4.7mb, IMX260 - 3.5mb.
Winner: Aside from the left gearstick, the Britecell again handily takes this. There's just more overall detail retrieval.
Comparison 4 - Right
Comparison 4 - Left
Comparison 4 - Top
Comparison 4 - Bottom
5. Britecell - 6.2mb, IMX260 - 6.1mb.
Winner: Too close to call, though this does show off the added blur with background objects with the Britecell.
Comparison 5 - Right
Comparison 5 - Left
Comparison 5 - Top
6. Britecell - 4.5mb, IMX260 - 4.8mb.
Winner: This one easily goes to the Sony. More detail and less noise.
Comparison 6 - Right
Comparison 6 - Left
Comparison 6 - Bottom
7. Britecell - 5.2mb, IMX260 - 5.1mb.
Winner: Whilst I feel the colour balance is more true to life with the Sony, the Britecell wins it in being a bit more consistent with detail.
Comparison 7 - Right
Comparison 7 - Left
Comparison 7 - Top
Comparison 7 - Bottom
8. Britecell - 4.3mb, IMX260 - 4.0mb.
Winner: This one's very close, but breaking the file size rule, the IMX260 edges it out with less noise and a slight sharpness advantage in areas such as the wheels.
Comparison 8 - Right
Comparison 8 - Left
Comparison 8 - Bottom
9. Britecell - 3.5mb, IMX260 - 3.5mb.
Winner: Again, perhaps too close to call, though the colour balance is a touch more accurate with the Britecell.
Comparison 9 - Right
Comparison 9 - Left
Comparison 9 - top
Comparison 9 - Bottom
10. Britecell - 3.6mb, IMX260 - 3.4mb.
Winner: The Brightcell takes this with less noise and sharper details.
Comparison 10 - Left
Comparison 10 - top
11. Britecell - 4.9mb, IMX260 - 5.3mb.
Winner: The Brightsell has the sharper foreground (chairs), but the Sony has far more in focus, especially on the left side distant objects. Overall the edge goes to the IMX260.
Comparison 11 - Right
Comparison 11 - Left
Comparison 11 - top
Comparison 11 - Bottom
12. Britecell - 4.9mb, IMX260 - 5.3mb.
Winner: Same situation here with the foreground focus versus the background focus, but overall with slightly more detail retrieval the IMX260 takes it.
Comparison 12 - Right
Comparison 12 - top
Comparison 12 - Bottom
Thanks for viewing!