Building an app that rounds given user's credit card purchases to the dollar and gives the remainder to charity. Which API's are available to me?

Question

I am trying to build an app that takes user's credit card information credentials, intercepts each of their transactions, and rounds the transaction up the nearest dollar. It will then give the difference to a charity.

Are there any API's available that will allow me to do this with popular credit cards or bank cards like Capital One or US Bank? Or does privacy policies at banks completely disallow this kind of API from existing to the average developer?