"I can't seem to find a link to a test video of the skycrane. It seems like they have never tested the whole system -- the best I can find is the crane extension part, when the thrusters are not firing.
Also, they didn't go with airbags because the…"
"why do you need public IPs from the telco? You can send a 'push notification' to your app from a server. On iOS it's the push notification API, not sure what it is on Android but there's an equivalent."