Discover is adding Apple Pay support starting 9/16/2015 and as a bonus, you get 10% cashback bonus on all in-store purchases made on your Discover Card via Apple Pay. See Press Release here.
From September 16, to the end of the year, cardmembers who pay with their Discover card using Apple Pay will automatically earn an extra 10% Cashback Bonus on up to $10,000 of in-store purchases. Discover it Miles, Miles and Escape cardmembers will earn an extra 10 miles per dollar on up to $10,000 of in-store purchases.
To make the deal even sweeter, Discover has extended their Double All Cash Back Your First Year Promotion for new users til 9/30/2015, effectively making your cashback 20% whenever you use Apple Pay to pay in-stores.