The idea is that you can create on main template on any theme then share different versions of it scaffolded to suite the needs of particular groups. See how to quickly and easily give different apps out to different groups of children.
If you're doing non-chronological report writing then this approach really comes into it's own as you can scaffold writing directly within the app. In other words, you may make 3 apps on the same theme but they each scaffold learning to greater and lesser degrees according to how your children are working.
Watch a teacher (below) share 3 differently scaffolded apps to 3 different groups in 30 secs within same class.