We are looking for the way for real-time synchronization of multiple external devices through wireless SD cards embodied in the sensor (Cameras, sensors, etc).
One of our earliest effort to gain the full control is on Eye-fi and its hack iii. I first ported iii codes for Mac. After downloading their codes, run autogen.sh there. It will complain missing packages, which mostly you can find in MacPort (Run 'sudo port install missing-packages'). For libarchive installation, I used the code at github. In my case, it couldn't find autosprintf library which were located at /opt/local. The workaround I applied for compilation is
./configure CXXFLAGS="-I/opt/local/include -L/opt/local/lib"
You will find binaries (iiid, iii-extract-riff-chunk) under src sub-directory.
We can find more info on Eye-fi hack (exact keywords to google). And later will add more if using otherwise iii.