True Tone

True Tone is Apple's feature for adapting display color and intensity to ambient light. On supported devices, sensors help the displayed white appear more natural in the surrounding environment.

It differs from Night Shift's warmth setting and schedule, and from a fixed reference white point used for color work. Availability depends on the Mac and display; an arbitrary external monitor does not gain a sensor through an app setting.

BetterDisplay exposes the system setting where available and temporarily disables it for upscaling calibration. See System Colors, Image Adjustments and Apple's True Tone guidance.