How do I add/remove credit cards?

You can save a credit card here on sj.se or in the app and you can remove credit cards if you log in to My page.

You add a credit card when you make a new purchase, by clicking on Save payment details in connection with entering your card details. 

To remove a saved credit card, you need to log in to your account. Click on Account, select Account Settings > Saved Payments Cards, then click Remove.