Wallet is an iPhone app that is used to store your credit card for use with Apple Pay. Find out more about using Wallet here
American Express will not charge you for using Apple Pay. Using Apple Pay requires an internet connection so you should check with your mobile phone provider directly to determine if there is a cost associated with your internet service
Apple, the Apple logo, iPhone and iPad are trademarks of Apple Inc., registered in the US and other countries. Apple Pay and Touch ID are trademarks of Apple Inc.