Are there good shiny or specular Unity shaders for Android
Well. The CG shader code in unity is automatically converted to OpenGLSL when building to iOS or Android. Hence any build in Unity shader should work.
Alternatively write your own shader. This does however have a steep learning curve. Getting a first result on a specular highlight would require you to read these chapters of a CG wikibook.
Implementing a minimal shader and Smooth Specular Highlights.
Yet again, if you are looking for reflective surfaces, tutorials on that can be found as well. However they do not reflect things in the scene, but a cube map tied to the shader.
Hope this can help