For example, if the user of an e-reader or smartphone wants to share a book or picture with someone else, that person’s phone will transmit an audible signal that can be received and decoded by other devices within earshot. The decoded signal contains information (such as a URL) allowing the receiving device to download the shared content from a remote server.

via ‘Bezos Beep’ could replace the smartphone bump for mobile content sharing – GeekWire.

LOL.  Someone reinvented the 300 baud modem.