Smart Watch Ambient Mode

[Carl Fredrik Ahl]

Hi,

Let's say that the watch in this example is AMOLED so that the battery usage depend on the color of the display:

When smart watches go to ambient mode the background of the screen turn dark (in most cases, some just reduce brightness of the screen) and the rest of the watch face turns white. I wonder why the rest of the watch face turn white, which is the most battery consuming color to display, rather than red for example, which only require the red led to light up? I know that it's easier to see white, but red would save more battery.