True Tone is a lighting feature on iPhones that adjusts the color and intensity of the display to match the ambient light. It uses advanced sensors to detect the lighting conditions and adapts the screens brightness and colors accordingly. True Tone is on by default, but it can be enabled or disabled in the Settings or Control Center. When True Tone is enabled, the display appears more natural and accurate, and images are easier on the eyes. If you turn off True Tone, the display keeps color and intensity constant, regardless of changes in the ambient light. Some people prefer to turn off True Tone because they prefer static colors, while others find it enhances the visual experience, especially when reading or watching content for extended periods.