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Consider a UICollectionView with flow layout and horizontal direction. By default, cells are ordered from top to bottom, left to right. Like this: 1 4 7 10 13 16 2 5 8 11 14 17 3 6 9 12 15 18 In my case, the collection view is paged and it has been designed so that a specific number of cells fits in each page. Thus, a more natural ordering would be: 1 2 3 10 11 12 4 5 6 - 13 14 15 7 8 9 16 17 18 What would be the simplest to achieve this, short of implementing my own custom layout? In particular, I don't want to loose any of the functionalities that come for free with UICollectionViewFlowLayout (such as insert/remove animations). Or in general, how do you implement a reordering function f(n) on a flow layout? The same could be applicable to a right-to-left ordering, for example. My approach so far My first approach was to subclass UICollectionViewFlowLayout and override layoutAttributesForItemAtIndexPath: : - (UICollectionViewLayoutAttributes *)layoutAttributesForItemAtIndexPath:(NSIndexPath *)indexPath { NSIndexPath *reorderedIndexPath = [self reorderedIndexPathOfIndexPath:indexPath]; UICollectionViewLayoutAttributes *layout = [super layoutAttributesForItemAtIndexPath:reorderedIndexPath]; layout.indexPath = indexPath; return layout; } Where reorderedIndexPathOfIndexPath: is f(n) . By calling super , I don't have to calculate the layout of each element manually. Additionally, I had to override layoutAttributesForElementsInRect: , which is the method the layout uses to choose which elements to display. - (NSArray *)layoutAttributesForElementsInRect:(CGRect)rect { NSMutableArray *result = [NSMutableArray array]; NSInteger sectionCount = 1; if ([self.collectionView.dataSour

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