I understood that the UV stretch function is to show the scale of stretch of the UVs. However, what would be the advantage of using angle/ area over the one ? or should we just use both to access the UVs internal stress after unwrap and what particular scenarios will be best for the use Angle/ area of UV stretch display ?
Area is great for determining whether or not the faces and islands have roughly uniform texel density so that the the resolution is about the same throughout the model. It's not really so much about stretching itself even though it's called that. Angle is used more for determining stretching and making sure the UV's aren't skewed so the pixels don't become smeared and blurry on the model. Does that help clear things up?