Connecting via ODB? Come on. The car does not need any of that built into it. You can connect an app on your phone to handle all of that and just use the screen as a display. There is no need for a car to have a cellular connection just to give this functionality. That would also prevent the car from being able to communicate with the mother ship. If there's an update, have the app do that as well.
> ODB
Ol' Dirty Bastard? I jest, but I think the theory behind wanting an 'On-board Diagnostics' [1] connection would be to get data from the vehicle. You can get cheap bluetooth OBD-II adapters to transmit that info to your phone, it's not a given. I don't know much about electric cars, but if you want your phone to know the fuel level in an ICE vehicle then you'd need this kind of connection.
[1] https://en.wikipedia.org/wiki/On-board_diagnostics
I make typos like that lot. The one that is most common for me is CVS instead of CSV. No, this isn't a list of things to get from the drug store ::facepalm::