The features listed below are supported on mobile platforms:
Linear HDR lighting.
Directional lightmaps (normal is taken into account).
Distance field shadows + analytical specular on sun.
Image based specular lighting - nearest reflection capture is applied to each object, without parallax correction. So there can be seams between objects.
Dynamic objects receive lighting correctly but do not cast shadows.
Supported Light Types
Mobile platforms only support a subset of the light types available in Unreal Engine. These are:
Stationary Directional Light
Directional Light with Mobility = Stationary. Best quality.
Static Directional Light
Directional Light with Mobility = Static. Best performance (no distance field shadows or sun specular).
Static Point Light
Point Light with Mobility = Static.
Static Spot Light
Spot Light with Mobility = Static.
Disable any ambient cubemaps you have in your post process volumes (set intensity to 0).
Place SphereReflectionCaptures in the areas that you want to capture lighting. You do not need a lot of these, just where there are unique surrounding lighting situations.
Make sure your materials are setup for reflections: interesting normalmap, varying roughness, nothing plugged into specular, and metallic of 1 or 0.
Right now, each mesh component gets assigned to the closest reflection capture. That means there will be seams in reflections between objects, and sometimes a large mesh will use an undesirable reflection capture that happened to be close to the mesh's center.