If you have an iPhone 6 or better (2/3 of iPhone users in the USA do), you have Apple Pay. It is a fantastic, secure and simple way to pay for goods and services both in-store and online.
Your credit card number is not stored on your iPhone, nor is it transmitted to the merchant. It simply initiates a transaction between the merchant and your bank and you approve the transaction with your fingerprint!
I have used it quite a bit and it is way, way easier and much more secure than using a credit card.
Apple just released a how-to video about Apple Pay:
If you want to learn more about Apple Pay, read this: http://www.apple.com/apple-pay/
Get ready for the holidays - set up Apple Pay on your iPhone now!