Color gamut in Xcode 8

Today I have installed Xcode 8(beta) and exploring Storyboards. Here we can now set background and tintColor for different traits. That's good news.

But here with trait collection(for example any height X any width) there is another selection of gamuts

Here is the screenshot

As I have searched for gamut, I found that it is related with color. I have tried with different combination of gamuts but I am unable to see any difference.

The documentation is also not helpful.

The question is how the developers get the benefit of this feature?

Developers can get benefit from it because it gives a much greater control over your app's color profile. You can explicitly assign a color to display depending on the device's gamut.

A solid understanding of gamut is key here. Devices will distort "untagged" colors, that is, colors outside of their gamut. The P3 gamut has a more extensive range of display colors than the sRGB gamut. This graph should give you a good idea of exactly how much more extensive it is:

So if you create your designs on a monitor with a P3 gamut, say a Cinema Display, your colors may display differently on a device with sRGB gamut. However, it's entirely possible there is no change in the color if you pick a color that is within both gamut.