Luke Zhao with a new view controller transitioning library that looks very impressive. Based around the Keynote concept of "Magic Move" this library makes it easy to animate element(s) of one view controller on to another. This is a simple solution to a problem that's tricky to do with the standard APIs.
I first posted about IGListKit a few weeks ago in Issue #272 and maybe you tried it out already? Or maybe, you took a look at it and moved on. I think articles like this one by Rodrigo Cavalcante are really valuable as they show the actual steps that are needed to get started without the transition feeling impossible.
A new library from Krzysztof Zabłocki for dynamically modifying your app at runtime, even supporting Injection (mentioned earlier in this issue). He's also put together a blog post with some thoughts on the why and how of how this came to be developed.
Jordan Morgan on writing code that fits both the Objective-C and Swift naming conventions at the same time. I hadn't come across NS_SWIFT_NAME before but I love the idea that naming of your library code doesn't need to suffer in either language.