Can there be any method of doing this?

This site is http://kennethreitz.com. Its driven by some moderate PHP on the top Wordpress.

My choices are to identify when the user is applying an apple iphone, and when they're either

a) tell wordpress to load another "theme" which i wrote. b) if the is not possible, possess a different wordpress installation on the subdomain (i.kennethreitz.com) that works from the same database, that utilizes another theme.

I'd rather have the ability to perform a for Search engine optimization reasons.

Any ideas?

Perhaps you have checked out iWPhone?

It is a Wordpress wordpress plugin and theme that instantly takes proper care of discovering if the customer comes from an apple iphone and formats things properly. Pretty simple to substitute your personal custom apple iphone CSS if you would like, even though fundamental theme is fairly decent.

Additionally, there are WPTouch which looks to become similar in functionality but is a little newer and it has better administration integration.

This is a Wordpress wordpress plugin which serves different styles to various browsers (e.g. apple iphone):

http://code.kuederle.com/browserbasedthemes

http://www.nathanrice.net/blog/serve-ie6-visitors-the-default-wordpress-theme/ demonstrates using template filter to dynamically alter the WordPress theme (within this situation IE6, but it may be for any mobile user agent):

add_filter('template', 'serve_default_to_iesix');
add_filter('option_template', 'serve_default_to_iesix');
add_filter('option_stylesheet', 'serve_default_to_iesix');

function serve_default_to_iesix($theme) {
    if(strpos($_SERVER['HTTP_USER_AGENT'], 'MSIE 6') !== false)
        $theme = 'default';
    return $theme;
}

I do not have knowledge about WordPress, however the iWPhone plugin + theme appears like it could work

As they are you can't do whether or B.

Loading another theme isn't feasible as that choice is saved within the database underneath the wordpress_Options table. This setting is site wide not per user. Option B isn't a choice either since you'd be discussing exactly the same database you'd be choosing exactly the same value for that theme.

Should you try looking in the wordpress_options table the theme setting is going to be based in the record that matches "template" and "stylesheet".