Face retouching can make skin look smoother, eyes look brighter and teeth look more white.
It's is only visible in the simulator window - not the main view.
To add retouching:
- Insert a Face Mesh.
- Add a new Material to the face mesh.
- Select the new Material.
- Select Retouching Material from the Shader Type dropdown in the Inspector panel.
- Adjust the sliders to brighten eyes, whiten teeth and smooth skin.
You can also follow this video tutorial.