Health is a diverse, messy, market. Apple's schtick has always been making devices that make computing magical, and health would be a huge shift away from that.

IMO the market is really looking for a a powerful all-in-one diagnostic health appliance - something like the analyser Theranos was pitching for, but which actually works, and is more comprehensive.

De-industrialising health and making the personal equivalent of a diagnostic lab that could keep track of key markers, watch nutrition, exercise, and supplements, and transfer information to doctors - AI or human - would be a major breakthrough.

But the technology for that doesn't exist yet. And even it becomes available it may not be affordable or portable.

And because bodily fluids are involved it conflicts with the Apple image of clean minimalism.

That leaves health as set of tentative fragmented tools and services which provide reassurance here and there - like the fall notification in Watch - but are a long way short of a comprehensive service.

The fitness market is a more obvious choice. But if you look at Apple's record, it's not inspiring. Fitbit is a strong competitor, because Watch hasn't lived up to its potential - possibly because Apple can't decide if Watch should be a fashion statement or a personal fitness device. It doesn't really make sense to consumers to try to sell it as both.

Behind all of that, I just can't see the current management team having the skill or imagination to make it happen. I think health is going to remain a side interest - a nice add-on, but not a huge new core market that Apple can expand into.