Where the Mailstream Meets the Inbox: The convergence of print and digital has been much-discussed in recent  years, but what exactly does that mean? There are of course 
QR codes, 
near field communications (NFC) and 
augmented reality  solutions—all in various stages of market maturity. The U.S. Postal  Service (USPS) is working on solutions of its own. The goal: to digitize  mailboxes.