Pytorch - ONNX - mobile vs Pytorch#jit - mobile

I saw at least two ways to export pytorch models to android device namely via transfering a model from Pytorch to Caffe2 and exporting a model with jit module.

What’s the difference of the ways?
Which of them in which situation is preferable?

Using torch.jit.script or torch.jit.trace is preferable to using Caffe2. The Caffe2 mobile engine is not being actively developed.