Is it possible to change the colors used by Color.primary and Color.secondary or are those only controlled by OS?
They are static properties that are controlled by the OS, with the color displayed depending on context (e.g., heading vs. general text) and the user's system settings (such as dark mode vs. light mode).
As you may know, you can set an
accentColor which is a broad theme color that is applied to views and controls. May or may not get you in the direction of what you're trying to achieve:
Is it correct that the way to change "accentColor" is to open Assets.xcassets and change "AccentColor" (different case)?