How do I update my payment method if I signed up through iOS?

To change your payment method for Yummly Pro on your iOS device, go to Settings > tap on iTunes & App Store > Tap on Apple ID: [Your Email Address] > Tap on View Apple ID > Scroll down and tap on Subscriptions > Tap on Yummly Pro > Tap Manage Payments > Tap the credit card on file that you want to manage > you can tap Remove or edit the information on file.