Validate.php
public static function isMobilePhoneNumber($phone)
    {
        $phoneNumber = substr(Tools::removeSpace($phone), -9, 1);

        return (!self::isCzechPhoneNumber($phoneNumber) || ($phoneNumber === '6' || $phoneNumber === '7'));
    }
public static function isMobilePhoneNumber($phone)
    {
        $phoneNumber = substr(Tools::removeSpace($phone), -9, 1);

        return (!self::isCzechPhoneNumber($phoneNumber) || ($phoneNumber === '6' || $phoneNumber === '7'));
    }
Check if the phone number is mobile

@param string $phone Phone number

@return bool Is phone number mobile
@static