Optimizing bump map or luminous textures on spheres for mobile

The materials look good on my PC and on the OpenGL ES2 emulator... but on mobile, it doesn't look as good. I am wondering if there are some techniques to optimizing mobile textures, or should everything (bump, normalmap, etc) be pre-baked into a flat diffuse texture?

Take the images shown here for example. Ignore the water and sky, just look at the sphere -- the PC version shows much more detail, while the mobile version is faded, looks as if everything has been badly mapped to diffuse

You sure the device (which device we're talking about by the way?) is not running in OpenGL ES 1.1?

In current Unity version (3.1), for example, iOS build target defaults to OpenGL ES 1.1. Which generally means complex shaders (like bumpmapping) are not supported.