Can I use different resolution for ui and scene on mobile?

Hi, for some low end device, I have to use low resolution to make game fps stable. However, when use low resolution, the ui became blur either.

Is there a way to use separate resolution for ui and scene on mobile? For instance, scene use lower resolution while ui use full resolution.

It seems ScenePercentage does not work on mobile.
Is there a simple way to render all the scene plus postprocess into one lower resolution RT and all the Slate in backbuffer so I can keep ui clear while have acceptable FPS?

Would be cool - did you find an approach? I have to have clear UI but at the moment this means sacrificing the in game visuals quite a lot for fps.