I racked my brain for weeks trying to figure out how to charge my iPad while flying. I never figured a way to do it, with Y cables, etc. Infound it to be a rabbit hole.
Then I found a little button in DJI Go4 that asks you if you want to charge while flying. Three options: No, Smart, Continuous. Works fine. Problem is this: the battery in the standard Mavic 2 controller is anemic. I burn three flight batteries with no charging and the controller battery is so low I can’t fly a third battery. My iPad will easily outlast the battery in the M2 controller.