iPhone shaders description? (iphone standard assets)

Pardon my ignorance, but Is there a description of the different iPhone specific shaders (from the standard assets package) somewhere?

I am particularly intrigued by the one called ‘background’.

oh, and are the particles ones optimized for iPhone, or just a renamed selection of the ‘regular’ particle shaders?

bump

It is a very cheap shader. It draws one texture, no lighting, and is rendered behind all other meshes.

The built-in particle shaders render both sides of a polygon. The particle shaders in the iPhone Standard Assets only render the front side of a polygon, so they’re cheaper.

excellent, thanks Daniel!