Samsung Pay is an interesting approach to this whole mobile payments thing. You don't have to wait on retailers to roll out support. Sure, you can use NFC in stores that are hip enough for such shenanigans, or you can use magnetic secure transmission (MST) to pay at terminals that would otherwise only accept debit and credit cards.
Samsung Pay launched last month, but the feature wasn't actually usable until carriers enabled support. And they did, except for Verizon Wireless. Well, now the hold out is pushing out updates to the four Samsung devices that have the hardware necessary to use MST: the Galaxy S6, S6 Edge, S6 Edge+, and Note 5.