Loyalty cards app
When information on this app was first posted on the viphone list 3 years ago, it covered merchants in the U.S., Canada, U.K., and Australia. I don't know whether present coverage has expanded. It's mostly used in the U.S. and Canada, I think. Add your entries as "Add Plastic Card". If you don't find your merchant listed when you search, choose "Other". There's a table index along the right side of the "Add Card" screen if you want to navigate the letter headings faster.
App Store URL is: