For now this is just a proof of concept and but with some time invested this could be good.
My idea is to create a iOS app similar to TouchOSC that communicates using sound. Like a 56k dial up modem. It would be built with the arduino in mind. The arduino would just need a library to interpret the audio into usable data.
The picture is proof of concept all I did was connect a 1/8 inch headphone jack to a three pin headers. Then with my trusty breadboard I connected the 1/8th ground to arduino ground and one audio channel to analog0. Then I just played some notes on my ocarina app and watched the digital waves over the serial readout.
If anyone has a Mac and some experience making apps and would like to collaborate or even take the project over let me know.
That is a very very cool idea.
I started to research this a little and came across a post where someone has already implemented this:
I'm new to arduino, this is yet another item thats going on my must build list
It would be interesting to integrate this with XBee or something similar, so that your iOS device with a small headphone jack attachment (arduino mini perhaps?) could communicate wirelessly with a set of sensors.
Bluetooth LE is of course another option, but its only available on the iphone4S (and perhaps the 'new iPad') and you'd have to build your own bluetooth le shield for the arduino.
The link you posted sends the signal the other way that's awesome. What this means it's possible to communicate both ways using this method. We just need a good iOS app and Arduino library.
If you have an ethernet shield you can also use the Ardumote app. The app can send UDP packets to the ethernet shield. The app allows the user to place customizable buttons and sliders that send certain packets to the Arduino over a LAN.
