I think smartwatches are smart enough to notice when they're not on your wrist any more.
P.S. Even without smartwatches, I would be greatly surprised if there is no remote-monitoring medical device which you strap onto yourself and which alerts someone if it thinks you're in trouble. The market for live-alone elderly people is huge.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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