I mean, for what it's worth, the head unit I'm using stores whatever I was doing in RAM so when it powers back on, ECUtek comes up. But you still have to reconnect, as bluetooth loses power when the car shuts off. This is as simple as clicking "My Car" and then "Dashboards"
https://www.amazon.com/ATOTO-Navigat.../dp/B075W9H5P3