My phone has a Micro USB, Micro HDMI port on it if that helps. The reasoning for this instead of just using a tablet is the fact that everything is already centralized on my phone. It makes far more sense to me to use one device to do everything and just extend from it. All my important data, files and music is in one location easy to update and use where ever I go. Sure there are cloud services that can do this but they are mobile data intensive and data is expensive in canada. If I use a tablet everytime I want to update, change or alter music, important notes or do anything else that involves the changing of librarys I then have to do it on every device I have. I'm trying to minimalist my devices as well.
If I get a tablet in my car I know alot of time I will end up reaching for my phone anyway for making calls and doing other things. Another important reason is this way with the OBDlink MX the bluetooth runs just through the phone so I can remote start it from outside the car, get in plug in the phone (which I do anyway) and one or 2 other cables and its all centralized and good to go. I would rather run some cables under the dash to the cupholder bays and mount the display then have to constantly miss out on stuff because my 2 devices are running dif apps and one has a more out to date music list. Might sound crazy to you but I would find that infuriating. Or spending time in my car moving data from and 2 the tablet every time I wanted to update/change things.
then I got to worry about the tablets memory and all that, and someone swiping it. but a monitor that is relatively cheap would be fine. if they did steal it really the window they broke is the bigger concern, as there are lots of cheap good res bright monitors coming out of china.
Plus tablets dont run direct 12DC so the tablet prob would not have a auto on and auto shutdown feature that most 12v dc monitors can do.
Only reason I can think to get a tablet is the battery and the GPS, but who is to say the gps will be better then my phones? and battery I can allways just install one if I cant get a monitor that has a internal one, and I can prob get a better GPS with a good sized antenna on a monitor.
anyway that is sort of my viewpoint on it. tablet is good in some ways but in others its sort of a drag. I would rather prefer to use my phone for everything.
So I could use the micro HDMI to run the display, I would need a USB to run the touchscreen? can that ever be done through bluetooth or through the HDMI? if not I would need to get power to run back to the device in host mode or get a usb splitter that goes from 1 to 2 and then dock it in that way?
Music could just run into the aux as always. as for the mic don't have that figured out yet, if your running touch through USB is that all that USB will do? or can it multitask and run other things through it as well?
Now If I can slave a cheap android tablet to my phone that would be something I would consider.... I could get a cheap capable android tablet easy from china for under $50