How a apple payment transaction works...
Apple Pay provides a sleek way for consumers to make payments with their iPhone, but perhaps the most innovative aspect of the payment feature — and its biggest potential value to consumers — is its security framework for preventing card fraud. While security remains one of the top reasons why consumers haven't adopted mobile payments, it's challenging to explain why one payments solution is more secure than another due to the complexity of payments security. In in-depth research from BI Intelligence we give an easy-to-understand breakdown of how Apple Pay security works and its implications for the payments ecosystem as Apple Pay and similar technologies become ubiquitous.
http://uk.businessinsider.com/apple-pay-is-ringing-in-a-new-era-of-payment-security-2015-5?r=US&IR=T