See Previous posts about this new system I've been working on. This new diagram shows 12vdc and 5vdc devices as well as the Samsung Galaxy Note II (7" display) and some of the layout for the networking involved. The "Driveby" app requires internet access to display the online Google Map data being plotted. This is not required to do a drive test run, but should be nice to have. The Galaxy Note II has built in LTE networking, the addition of a OTG USB adapter and a wired internet cable will allow access to the private network.
I'm not sure yet if I'll be able to run both at the same time, but that's the plan at this point and kind of important if I intend to be able to display the maps while driving.
Click on the Image to see a larger version.