Because my OP actually comes up with some potential devices and I'm asking if such devices could have success. U just said u don't see them being successful without putting any form of thought into it.

I want u and others to think outside of the box and come up with some ideas u think Nintendo will try implementing and base ur answer off that, not just a basic yes or no response based on nothing.

I don't see QoL doing anything for Nintendo now. The mobile market is sapping up that crowd. I think Nintendo would have had a good shot a year or two ago, but with the iWatch etc now all hitting the market place and the plethora of fitness apps (from exercise, to diet etc.) already on iOS and Android, a separate device for this stuff no longer has a place in the market, just like if TomTom and Garmin etc were just hitting the market now, they'd find Sat Navs a very tiny niche rather than the boom it was 10 years ago.

QoL has nothing to do with gaming

Actually, I've put quite a bit of thought into it.  Was going to make a longer post just now, but since MikeRox put it so perfectly, I'll just agree with what he said.

QoL will have nothing to do with gaming. It won't help them in the gaming scene. And as much as it pains me to say, if its a physical device at all outside of a wearable sensor, I doubt it will take off in the west. There are already fitness apps out there that cover many different things. Body building, weight loss, diet, general lifestyle etc. All of these things are things that Nintendo are not a world leader in.

As for the sleep sensor I think its intriguing technology. I think if they can work on the scanning better, it could be used in the medical field as a tertiary device. It apparently can track heart rate and breathing and the like.

They did their thing with Wii Fit and their education games but this is on another arena and I just don't think they'll be able to compete.