wp_is_mobile()

if(wp_is_mobile()){
	echo '正在使用移动设备浏览';
}else{
	echo '浏览使用的不是移动设备';
}

function wp_is_mobile() {
    if ( empty($_SERVER['HTTP_USER_AGENT']) ) {
        $is_mobile = false;
    } elseif ( strpos($_SERVER['HTTP_USER_AGENT'], 'Mobile') !== false // many mobile devices (all iPhone, iPad, etc.)
        || strpos($_SERVER['HTTP_USER_AGENT'], 'Android') !== false
        || strpos($_SERVER['HTTP_USER_AGENT'], 'Silk/') !== false
        || strpos($_SERVER['HTTP_USER_AGENT'], 'Kindle') !== false
        || strpos($_SERVER['HTTP_USER_AGENT'], 'BlackBerry') !== false
        || strpos($_SERVER['HTTP_USER_AGENT'], 'Opera Mini') !== false
        || strpos($_SERVER['HTTP_USER_AGENT'], 'Opera Mobi') !== false ) {
            $is_mobile = true;
    } else {
        $is_mobile = false;
    }
 
    /**
     * Filters whether the request should be treated as coming from a mobile device or not.
     *
     * @since 4.9.0
     *
     * @param bool $is_mobile Whether the request is from a mobile device or not.
     */
    return apply_filters( 'wp_is_mobile', $is_mobile );
}