This technology isn’t new, and can be used for more purposes than payments. Advertising companies have used this technology to send out inaudible marketing beacons from TV ads to nearby phones running specific applications for targeted advertising for years (yikes). Google has also implemented this technology in some of their products to automatically detect nearby devices. When it comes to payments, while there are more regulations and security concerns to take into consideration, it is still interesting to explore this space, and understand its opportunities and limitations."