Apple "Pro" iPhone models have had a frosted glass back material for a while now and I am not quite sure how to incorporate such a material in my models using Blender's standard shader editor.
Here are some examples of what I am going for. The first image is a render by Ian Zelbo and the second is what the material looks like in reality.
Here is what I have so far, rendered with Cycles.
I think my biggest issue is adding color while also retaining the physical characteristics of a frosted glass material. I have attached a link to the blend file containing the glass back object with the material.