Google SVP Sundar Pichai may have tipped the company's hand on mobile payments back in Barcelona, but he offered little detail on how the system would work. At I/O 2015, though, the folks in Mountain View served up a wealth of details on the matter, including the announcement that Android Pay would be part of the Android M release. Just like Apple Pay, transactions are sorted via NFC and your actual card number isn't shared with merchants. Instead, it'll use "a virtual account number" to handle payments. When it arrives, the system will be employed by over 700,000 retailers (sounds familiar) like Macy's, Whole Foods, Walgreen's and many more. It'll also be used for in-app purchases, so if you're ordering food from Chipotle or paying for an Uber ride, you'll be able to use Android Pay there as well. And yes, web sellers can leverage the system, too.