I can get apps on my credit card

Apps run on ios devices, not credit cards.

Have you tried downloading the apps on an iOS device, not your credit card?

As I understand it, your credit card needs to be from the same country as the app store you're accessing (I use iTUnes gift cards, not a credit card)

Try using an iTunes gift card. Works the same as a credit card, but you don't have to worry as much about security (if a bad guy hacks your account all you lose is the balance on the card), nor do you have to worry about accidentally racking up large 'in app' purchases - like the horror stories you hear about people or their kids buying hundreds/thousands of dollars of smurfberries or the like.