It's doubtful that anyone has better low-power 3d capability than AMD.
I don't think we really know this, especially since AMD hasn't done an SoC suitable for phones. We don't really know who hits the best perf/W, perf/mm^2, and so on at phone appropriate ranges and requirements. DX11.1 support for instance is still overkill for phones, IMO - it's a bunch of stuff that the software won't be able to utilize any time soon.