Can someone explain camera drones to me?

You can have it so that the person can watch the video live, as it’s happening. You can also save it to watch it when it lands. I’m not sure if any smartphone can do that, you probably would just need one that wouldn’t require you to hold the record button down the whole time.
But yes, you can have it streaming the whole time if you want and can afford/get software.

Most of the drones link to your smartphone to stream the live camera over a wifi link while using standard RF for control. Most also can store video/photos internally on a flash card. You can also get VR headsets instead of using a phone. The reason phones are used is it’s much cheaper to use the hardware already built into your phone than to build a display and wifi into a controller. Your phone also is an internet link to the drone for firmware updates.

Also must add, your phone stays with you and is attached to the controller. It generally does not go with the drone.

Yeah, I was going to say, I think it’s possible to send your smartphone up in the drone. But I think that isn’t practical and that the drones wouldn’t require a personal smartphone