This is a PHP / MySQL application that you install on your web site to sell license keys and automatically deliver them to a customer after purchase from PayPal. These may be mobile pin numbers, key codes or be any other form of license codes.
PHP-KeyCodes provides the checking of the completed transaction before the codes are sent out to the purchaser by email. It is an automatic delivery system where the top license code or pin number is extracted and automatically sent to the customer without any intervention by yourself.
The application does not create the pin numbers themselves although there are a set of php functions which can be modified to do your own custom processing, for example, create a pin code based on the customer name.
The customer does not have to have a PayPal account to purchase an item but can use any supported Credit Card. PayPal then becomes just a payment gateway for the credit card.