> The GPS thing is the biggest hurdle you'll still have to clear. I don't have a great solution for you.

Sony also has a great smartphone app which doesn't eat any battery at all. It waits for your camera to connect and activates the GPS when it connects and feeds data to it. I have never seen it eat my battery more than it should on my old iPhone X.

Sony's app also can do remote shooting and image transfer via WiFi and it's not half bad at either.