If you have never played with the Kickstarter funded LoopPay, the following article does a good job of explaining how it works - interesting tech/hardware as it works with almost any swipe-type point of sale (POS) device rather than relying on NFC enabled POS devices.
The world's largest smartphone manufacturer said on Wednesday that it had acquired LoopPay, a mobile-payments technology startup. The deal potentially supercharges Samsung's ability to enable its customers to pay for goods and services with their smartphone, a feature that has generated more interest since Apple introduced its Apple Pay system. But Samsung has dabbled in mobile payments before -- years before Apple Pay. So what's different about LoopPay, and does it have a chance to be more successful? I played around with LoopPay's technology going back to last year, and have spoken with LoopPay's executives on multiple occasions about their product. Here's what to know, so far, about what it is and what it might mean for Samsung.
http://www.cnet.com/news/samsungs-looppay-what-it-is-and-why-you-should-care/