"It's not hard work, but it can take time to complete a shift, " says Ms. Jackson, 27, using the app's lingo for a set task.

WSJ: Apps Spawn New Jobs, Services

These included "people who are not prepared to work what has to be shift work, it's a service that has to be delivered seven days a week, 24 hours a day" and people "who are not prepared or who are not able to do the very personal, intimate care that's needed and that's particularly where wages are lower than we would like to pay".

BBC: British workers 'needed on farms'

It's a shift in thinking that is rippling through places of work, schools and homes as the very fundamentals -- chair at desk -- seem to cause harm when used for the lengths of time now considered normal.

CNN: Sitting for hours can shave years off life