1. A method to retrieve personal customer data of a customer for delivering online service to said customer:an online service supplier initiates the sending of a network identifier of a mobile node, used to communicate with the online service supplier and bound to the customer by a mobile network operator, to an application programming interface platform (API) with a request to retrieve the customer data,
the API platform identifies the mobile network operator of the mobile node, and forwards the network identifier and request to retrieve the customer data to said mobile network operator of the mobile node,
the mobile network operator uses the network identifier to identify the customer and sends the requested personal customer data contained in a data repository of the mobile network operator to the API platform,
the online service supplier retrieves the personal customer data at the API platform.