protected static function _matchAgentAgainstSignatures($userAgent, $signatures)
    {
        $userAgent = strtolower($userAgent);
        foreach ($signatures as $signature) {
            if (!empty($signature)) {
                if (strpos($userAgent, $signature) !== false) {
                    // Browser signature was found in user agent string
                    return true;
                }
            }
        }
        return false;
    }