Greetings! Thank you for the review.

May I ask how come some OLED smartphones measure to have a very high contrast ratio one would expect from this display technology, while some measure to have contrast in the ballpark of what's more typical for IPS (700:1-2600:1)? What might be the reason behind this? Is this some kind of mistake/artifact of the measurement process, or do some smartphones actually have a raised black level?

I tried looking for some factors that could maybe possibly influence this, like screen coating, presense a of pre-installed screen protector, and even display dimming characteristics (frequency and amplitude of the modulation) or who was behind the review (and actual measurement process I guess). But I failed to find any consistent trends.

Also, would you, by any chance, happen to know and be able to tell me at what refresh rate the display typically runs at when the color/grayscale test patches are being displayed during the measurement? Most modern smartphones have dynamically changing refresh rate enabled by default, which leads to luminance/"gamma" changes for intermediate shades (this effect is somewhat significant as the changes can be relatively easily detectable even by the naked eye). Hence color rendering characteristics constantly change slightly, unless the refresh rate is manually set to a fixed value. This, on top of all other relevant complicating factors like differences in ambient light levels and screen luminance in actual practical use, to name a few, makes assessing the expected color reproduction even less straightforward and certain.