Questions about the light map Type

I’m developing a mobile game using Unreal Engine 4.8.
There are various types of light maps in Unreal engine.
I’m curious which types we can use in mobile environments.
If I select Stationary light, ShadowMap is created, and SkyOcclusion for SkyLight.
There are HQ, LQ LightMaps as well.

Like this, various light maps can be created.
But I’m curious how these light maps are used, and whether or not all of these can be used in mobile environments.
If not, are these excluded when packaging for mobile.

It seems that LQ and HQ are ordinary light maps like I can see in other engine.
When I see the texture file of LQ and HQ, it looks duplicated with different colors.
So I assume the texture quality would be reduced by half as the painted size would be half.
Is there a way to make this not be duplicated? or is there a specific reason for this duplication?

I would appreciate for your reply.