Great idea. For the folks wondering why this is a great idea, think “Internet of Things”. All manner of devices from home alarms, appliances all the way down to individual light bulbs can these days be controlled from your home network or the internet. Setting these devices up the first time is complicated, fiddly and proprietary. Imagine having a simple cell/tablet/pc app that lets you enter the configuration parameters, hold it next to the listening appliance and then click setup. Most folks that end up on forums like this know something about Bluetooth, networks or other matters technology, but 80% of other folks struggle getting their gadgets setup and working.
This idea is not only simplifying the user experience, but greatly simplifying how gadget designers implement configuration functionality into their products. Imagine the saving in time and money not having to build any user interface into say an internet connected $15 toaster [sic]. Setup is done locally via the phone via acoustic coupling by passing the configuration parameters directly to the toaster, and once connected the toaster is then managed via simple API (rest or SOAP web services sounds great). The user interface is built and run on the web where all manner if complicated and fancy looking human interactions is easily done without taxing the $15 toaster with this burden.
The idea is not new or unique. The Electric Imp guys are doing the same thing, but via light pulses from a cell phone screen. Personally I think the acoustic channel is more flexible and portable, all be it a bit more complicated and possibly slower.
I can imagine having a single on chip solution (with an ultrasonic mic) and a matching Cell/Tab/PC app that can be deployed in mass on these cheap devices for pennies.
I can smell a kickstarter coming on..
Source : https://hackaday.com/2010/02/01/android-audio-serial-connection/315