Solved by David_Reiss in post #2 
              
              
                What are the benefits of using Vulkan over NNAPI and vice-versa for running inference on GPU? 

The main difference is that with Vulkan, the code that runs on the GPU (shaders) ships as part of the PyTorch runtime.  With NNAPI, we give a high-level description of the model to the OS, which then sen…