this is a pretty straightforward question, but I haven\'t been able to find a definitive answer to it on SO (if I missed it, please correct me).
Basically, my quest
For anyone who has the same question:
I ended up using the UICollectionViewRightAlignedLayout library that @chinttu-roxen-ramani recommended. You can either set it with code:
self.collectionView.collectionViewLayout = [[UICollectionViewRightAlignedLayout alloc] init];
or through interface builder:

I ended up making a couple modifications to the library, but overall it works great.