The service is available on the Samsung Galaxy S6 and S6 Edge, the S7 and S7 Edge and the new S8 and S8+. A software update is also rolling out to this year's A3 and A7, and Samsung is promising support for additional devices "in the coming months." The big question, however, is why anyone would choose to use this over Android Pay. Samsung's version does support iris scanning for payment authorisation, which is a neat (and pretty secure) touch. But otherwise, there's little to separate it from Google's established service, which comes with handy deals and will follow you regardless of the Android phones you buy in the future.