Kersten Broich & Justus Kandzi with an interesting article on using a single table view controller to manage the UI for three states of a signup/register/login view. This might seem like a dubious idea at first but their method makes it pretty simple, and the resulting transitions between states are beautiful.
It's table view week this week! This article by Tom Harrington covers using a stack view inside a table view cell to expand/collapse when tapped. I think you need to be careful with usability when using expanding cells, but there's certainly a case for them and stack views with this method make them much easier to code.
Tomasz Szulc on building network architecture that isn't dependent on any third party libraries, or any Apple provided libraries like Core Data and which is easily extensible and testable. There's also a reference implementation on GitHub too. I like the design.
Whether you like the idea of splash screens or not, there's no denying that the animation in the new (ish) uber redesign is beautiful. Derek Selander breaks the animation down into its component parts and then rebuilds them from scratch.