I don’t carry my iPhone around with me in the house so from time to time end up answering incoming calls on my watch. Is it possible, once I’ve walked back to my phone, to hand the call off to the phone? This would be particularly useful for incoming FaceTime calls.
Yes. A button appears on your other device(s) to claim the call. I only recall using this with FaceTime but I'm fairly sure it works with all call types.