htaccess rules sntax pointer

[cyberjef]

I need to write a htaccess redirect for mobile devices that land on the index page.

I need a pointer to a decent guide.

For example:

RewriteCond %{HTTP_USER_AGENTfr"sony|symbian|nokia|samsung|mobile|windows ce|epoc|opera" [NC,OR]

What flags are available and what hash of environment variables are there?

I've been thrashing about looking through the myriad of resources on this, and I can't find that. Anyone have a quick link?

J