A buddy of mine pulled out two Mavic Air drones that He bought years ago and never flew. He has quite a few drones. I have plugged in the controller and battery. So far the battery seems to be charging and the controller is blinking…one light quite rapidly. The manual says nothing about that. It may be dead. We’ll see. If it’s not it may be a toy to lend friends but eBay and such are asking $200 for a battery so I doubt it’s going to get much flight time even if it revives . It also calls for the Go 4 app which I know nothing about but I’ll look into it if the battery in the controller ever charges. Any thoughts on the Go4 or other comments are welcome. I have an FPV, Mav3 and Mini 3 Pro with an Avata on the way so this would be a toy to lend friends. UPdate . The controller battery does seem to be charging. If anyone has a source for reasonably priced batteries it would be fun to have one or two others.