The MICO Shield makes it easy for you to create an Arduino project that interfaces with a cell phone. The Arduinocell phone interface unlock a whole new world of possibilities：projects where your Arduino can place phone and receive phone calls.
An example of aMICO project is where it receivesa phone call and presents the caller with a voice prompt："press 1 for lights on". MICO can then decode the caller's button press and take action、in this case turn an output on. Of course everything is customizable：MICO has a microSD card slot so you can store your own voice and all MICO libraries and sketches are open source、free to download and hack.
MICO interfaces to a cell phone's 3.5mm audio jack. MICO has no build-in cell module or antenna. Because of that、MICO provide some key advantages：Universal：can work on ANY cell network over the world！ GSM、CDMA、TDMA、analog…
Rich features：can utilize new features cell phones have. For example：on the iPhone、MICO can say commands to SIRI such as "post to twitter：temperature is 70degrees".（of course、you could instead just use an old phonefor basic function）
Simple：no need to learn complicated AT commands. Phone is controlled just with Answer/End Call Button and voice out of the microSD card.
Perfect for quick/temporary projects：no need to buy GSM card just to run a quick demo project. Just plug in your own/friend's phone. No need to tear it open to grab the card、or hack its software.
Feature
DTMF decoding IC
DTMF encoding play back recorded tone off microSD
Answer/End Call button（physical and Arduino controlled）
Play out sound to phone and to a headset
Works both newer AHJ（iPhone/Android）and older OMTP phone standards
