This is a great idea! I did it myself on a piece of paper just to understand the flow. Then I designed the Reviews myself just by following the flow of the Previews. It turns out that it's not that hard!! :)
The main idea behind this (at least how I have it in my mind):
1. There is a main controller (AppDetailController) that (depending on the section) will draw out a cell (ex. ReviewRowCell).
2. That cell (ReviewRowCell) will consist of some other elements (UILabels, UIViews, UICollectionViewControllers (if we want another collection view inside the cell), etc.). I am using a vertical stack view to stack all elements rather than using autolayout. I find it easier, faster and cleaner.
3. The UICollectionViewController that we modified for the snapping effect, will be responsible for drawing the "child" cells (ReviewCell) as a horizontal collection view.
4. Lastly, you design the ReviewCell by placing elements.
Hope I helped!