Not a cockpit error?
"no QA test plan can adequately cover the stupidity of the general public"
Mostly true perhaps, but it doesn't seem to apply here. This seems to be something that happens without the help of user stupidity -- other than the questionable user judgment involved in purchasing of an Internet connected "watch". The problem looks to be the questionable manufacturer judgment of collecting user data without understanding the actual risks and rewards of doing so.
Queue up Richard Feynman's Appendix F to the Rogers Report on the Challenger disaster wherein he analyzes the huge gap between Space Shuttle reliability estimates made by NASA management and those made by working engineers.