I’ve mentioned a number of open source projects providing custom UICollectionView layouts most recently a layout allowing you to create stacked card layouts like those in the Passbook and reminders apps.
Here’s an open source component providing custom UICollectionView layout that provides easy drag and drop reordering called RACollectionViewReorderableTripletLayout.
This layout features nice smooth reordering, notifications, and notifications for different dragging events, but the really nice feature is how when you swap cells the cells take the size and shape of the swapped cell.
You can find RACollectionViewReorderableTripleLayout on Github here.
A nice reorderable UICollectionView layout.