There really is a difference between the two. Thanks to Sammy's acquisition of Loop Pay and its MST (Magnetic Secure Transmissions), Samsung Pay isn't limited to retailers who have NFC supported point-of-sale systems. Samsung Pay will work with any retailer that swipes consumers' credit cards at check out. As a result, the number of stores that accept Samsung Pay dwarfs the number of stores that are compatible with Apple Pay.
Samsung Pay is available in the U.S. and in South Korea, and will soon expand to the U.K. and Spain. This was made official today during Samsung's European Forum 2016 when the European head of Samsung Pay, Nathalie Oestmann, told those in attendance that an announcement would be made at MWC, which kicks off officially on February 22nd.
The manufacturer will be holding its Samsung Unpacked 2016 event on February 21st, the day before MWC opens. Considering that we will see the Samsung Galaxy S7 and Samsung Galaxy S7 edge both introduced at that time, Samsung could also take the opportunity to announce the expansion of Samsung Pay into new territories.
The mobile payment service is currently compatible with the Samsung Galaxy S6, Samsung Galaxy S6 edge, Samsung Galaxy S6 Active, Samsung Galaxy S6 edge+ and the Samsung Galaxy Note 5.