2pk of Costco Photo Books using their app for $20

In order to encourage smartphone users to try custom photo book printings, the official Costco app (Google Play, iTunes; sorry, no Firefox OS marketplace app available) is offering a 2-pack of 8×8-inch custom photo books created from the pictures living on your smartphones for $20. Their page does not say whether this is restricted to members-only or not. It also does not state whether there is a shipping fee or free store pickup. The app can also be used to order conventional prints and canvas prints.