Mobile payments is the new battleground between giants Apple, Samsung and Google with their Apple Pay, Samsung Pay and Android Pay payments system, respectively (yes, a lot of Pays). Although the technology didn't really take off yet, it is slowly gaining its ground, since it is something relatively new when you compare it to the credit card industry as a whole, and not many users really know or are willing to use their phones to pay for a restaurant, groceries, coffee, etc. What they all have in common is that these systems work with wireless payment terminals and NFC chips inside each smartphones - users save their credit cards on the payment system and when the time comes to give their money away, the smartphone sends a signal to the wireless payment terminal making it possible for the payment provider to charge for that purchase. Many terminals out there still don't have NFC and Samsung has a great advantage over other payment systems, as the company have an exclusive technology that simulates the magnetic stripe of credit and debit cards, making it possible to use Samsung phones with Samsung Pay on almost any existing terminal out there.
If you have a Samsung phone compatible with Samsung Pay, it doesn't mean you can use it yet, as it is available only in South Korea and the U.S. The reason is that, in order for it to work, Samsung needs to make partnerships with local banks so debit cards can be used for payments too. When launched in the U.S., the system was compatible with Bank of America, Citi and U.S. bank, and as of now, clients of JPMorgan Chase can also benefit from Samsung Pay. This is really good news for Samsung, since it will increase the reach of their payment system.
However, as mentioned by The Verge, Samsung Pay and other payment systems are far from ready for replacing your plastic card. Although Samsung magnetic secure transmission (MST) technology can, on paper, work with almost any existing terminal, it still doesn't work very well and it is common to have encounter problem in making it read the signals sent by the phone, meaning you always need a backup plan. Additionally, terminals where you have to insert your card such as gas stations also don't work. Samsung Pay currently works with the company's latest flagship phones - Galaxy S6/Edge/Edge+ and the Galaxy Note 5, and for now is available only in the U.S. and South Korea. Samsung already said that the system should arrive soon in the U.K., Spain and China, with more countries to follow.