Lets say you want to post from your Android or Iphone WordPress clients to a custom post type instead of the the defualt ‘post’ type. Paste the code below in your functions.php and you should be good to go 🙂

function redirect_xmlrpc_to_custom_post_type ($data, $postarr) {
    $p2_custom_post_type = 'custom_post_type'; //Change this to the custom post type you are using for your blog
    if (defined('XMLRPC_REQUEST') || defined('APP_REQUEST')) {
        $data['post_type'] = $p2_custom_post_type;
        return $data;
    }
    return $data;
}

add_filter('wp_insert_post_data', 'redirect_xmlrpc_to_custom_post_type', 99, 2);

Change $p2_custom_post_type = 'custom_post_type' to the custom post type you are using for your blog.

Now I can post from my Android Phone to my custom P2 micro-blog 🙂