Samsung Pay was announced at Mobile World Congress alongside the Galaxy S6 and Galaxy S6 Edge, as Samsung's approach to mobile payments. It's been in testing ever since, as Samsung and card companies want to be sure that the mobile payment service will work as intended. The last thing Samsung wants is for a transaction to fail after you've left the store. Then the store is out of that money. According to a report out of Business Korea, Samsung Pay is now in Final Testing with about 8 local card companies in South Korea.
Unfortunately, the magnetic strips and fingerprint verification isn't working as great as Samsung had hoped for. And they are continuing to test it to be sure it'll be ready to go this September alongside the Galaxy Note 5 when that is announced at IFA. It's important that Samsung continues to work on Samsung Pay and make sure it's perfect, because there will be millions and millions of people using this, and one mess up, and it could kill the entire program. Which is unfortunate, but that's how things go.
Currently, the way that Samsung Pay works is your phone, likely the Galaxy S6 or Galaxy S6 Edge, replicates the card's information that is found in the magnetic strip on the back, and creates a magnetic field, that is used to activate a CAT or a Credit Authorization Terminal. However, this only works after a user has authorized it by using the fingerprint sensor on the device. Doing it this way means that someone with your PIN won't be able to use your Samsung Pay, which theoretically would have all of your credit cards and debit cards inside. Fingerprints are more secure than PIN numbers, but there's always that chance that a bug could ruin it.
This September, when Samsung takes the stage in Berlin, we are expecting them to announce that Samsung Pay is now available to everyone, along with announcing the new Galaxy Note 5, which seems like it's going to be a major hit. Although that shouldn't be much of a surprise really.