判断客户端是否是手机

function is_mobile(){
	$regex_match="/(nokia|iphone|android|motorola|^mot\-|softbank|foma|docomo|kddi|up\.browser|up\.link|";
	$regex_match.="htc|dopod|blazer|netfront|helio|hosin|huawei|novarra|CoolPad|webos|techfaith|palmsource|";
	$regex_match.="blackberry|alcatel|amoi|ktouch|nexian|samsung|^sam\-|s[cg]h|^lge|ericsson|philips|sagem|wellcom|bunjalloo|maui|";
	$regex_match.="symbian|smartphone|midp|wap|phone|windows ce|iemobile|^spice|^bird|^zte\-|longcos|pantech|gionee|^sie\-|portalmmm|";
	$regex_match.="jig\s browser|hiptop|^ucweb|^benq|haier|^lct|opera\s*mobi|opera\*mini|320x320|240x320|176x220";
	$regex_match.=")/i";
	
	return isset($_SERVER['HTTP_X_WAP_PROFILE']) or isset($_SERVER['HTTP_PROFILE']) or preg_match($regex_match, strtolower($_SERVER['HTTP_USER_AGENT']));
}

转自:http://snipplr.com/view/48763/simple-user-agent-mobile-and-smartphone-detection-and-redirction-with-php/