blackberry userAgent detection code

Here is the userAgent detection code for the blackberry:

if((navigator.userAgent.match(/blackberry.*/)))
{
location.replace("insertmobilesiteaddresshere");
}

Iphone/Ipod as well:

(navigator.userAgent.match(/iPhone/i)) || (navigator.userAgent.match(/iPod/i))

But does anyone have the palm, google phone..? or better yet one single code for all phones that can't read flash?

What does this code do?
Where do you put this?

Posted from my CrackBerry at wapforums.crackberry.com

Can we get a little more explanation as to what this does?