Samsung Pay: everything you need to know

The essential details for Samsung's mobile payment system

There's a smaller battle waging within the never-ending smartphone wars that Samsung just managed to heat up: mobile payments. The Korean mega tech firm has announced the release of Samsung Pay, its answer to Apple Pay and Android Pay.

While the service is limited to Samsung phones - and it's even more exclusive than that, but more on that later - it has a serious leg up on the competition through some clever tech and fruitful partnerships. Here's everything you need to know about Samsung Pay.

Samsung Pay

Samsung Pay at work during Unpacked 2015

When (and where) is it coming out?

Samsung Pay will launch in the company's native South Korea on August 20, but will arrive on US shores on September 28.

As for the UK, Spain and China, Samsung EVP and head of Samsung Pay Injong Rhee said during Samsung's August 13 Unpacked event that the company plans to roll out the service in those regions in "the near future," with partners to be named in each market.

However, keep in mind that this capability is already within Samsung's latest phones. These release dates are likely just a matter of Samsung and its partners flipping a few switches when it's go time.

Samsung Pay

Samsung Pay head Injong Rhee makes the grand introduction

How can I get it?

Now, here's where things might get a little sour for Samsung fans rocking even slightly older hardware. Shortly after Samsung's Unpacked event, a representative confirmed that Samsung Pay is only available on the following Samsung phones:

Essentially, any phone older than the Samsung Galaxy S6 will not be able to use the Samsung Pay service. (Available for all Android phones running 4.4 KitKat or later, Google's NFC-based Android Pay will work on far more of the firm's phones than its own Samsung Pay.)

That said, there's at least one possible reason to point to for Samsung Pay's limited availability.

Samsung Pay

This is where you'd tap your Samsung phone to use MST

How does it work?

If you own (or plan on owning) one of the shiny new Samsung phones listed above, your phone will work with Samsung Pay as soon as the service launches. All you'll have to do is register your credit cards of choice and start tapping at any point of sale (PoS) machine that accepts credit cards.

Yes, this means that Samsung Pay will work even if the PoS does not have NFC (or near-field communication) technology built-in. How? It's done through MST, or Magnetic Secure Transmission.

With this special MST antenna, all of the above Samsung phones can trick standard magnetic strip credit card readers into registering a tap as if you had swiped your plastic. It does this through generating changing magnetic fields over a very short period of time - think fractions of a second - emulating the data-filled magnetism that a standard credit card swipe would.

Samsung Pay

All of Samsung Pay's partners at launch on one massive screen

It's a neat trick, but one that understandably raises security concerns given the recent string of retail store data breaches in the US (ahem, Target). Samsung's Global Co-GM of Samsung Pay Thomas Ko was keen to reassure me that these antennas are neatly placed away from all other radios within its phones to avoid interference that might otherwise create security holes.

Speaking further to security, Ko went on to assure that all of the data transmitted in a given transaction is encrypted using a one-time token system. Each time a transaction is executed, the phone supplies a unique, ephemeral token to the terminal. When it then arrives at the associated banking institution's firewalled servers, the token is then decrypted and processed.

However, there's one small catch to all this. Because this tech relies on cooperation from the banking firms, only Visa, MasterCard and American Express will support MST-powered, wireless payments through Samsung Pay at launch in the US. (All of Samsung's launch partners will support the service through NFC, though.) Ko tells me that Samsung is actively working on expanding this feature to work with other institutions, like Chase, Discover and more.

Samsung Pay also supports gift cards and store-branded credit cards through the exact same method, not to mention NFC.