The "Lens compensation" apps is the one you must have. It improves the red shifts problem from VM 12, Leica 28 F2 and 21 F3.4. Details can read on Sony website. I am using it and love it﹗﹗﹗
I hardly shoot wider than 35mm so I guess this app is not a necessity yet... I saw the sony website and setting up the profiles seem troublesome to me...