All over where I read about the Collada file format I see some hint as to how integrated Collada is to OpenGL ES - or the other way. How integrated is it really? I suspect not, but are there functions that directly work with Collada files? - or even parts of Collada files? Or do I need to create my own parser from the ground up?
You need to create your own parser, OpenGL or OpenGL ES doesn't have any model/mesh loading functionality, that's the developer's responsability.