It's always nice to see people take components they have developed as part of building an app, and open source them. It's also a good chance to think about those components from the point of view of how other people would use them, which also makes them better for you to use. Ryan Nystrom did this in style this week with four(!) libraries extracted from GitHawk. Could you open source anything from your apps?
By introducing Markup in iOS 12, Apple have set expectations of what users will be able to do with images they bring into your app. You can't use Apple's Markup tools directly, but you could use this library by Steve Landey to achieve similar functionality. There's also a blog post introducing it.
You may have read Dave DeLong's series of posts on a better MVC back when I linked to them in Issue 327. You may also have seen him give conference talks on it too. But, if somehow you missed both those things, he's just released this implementation of a To Do app which uses the concepts he's advocating for. It's always great to see advice like this turned into something this practical!
There's a new UI element which is becoming increasingly common in Apple's iOS apps. You might have seen it in your search history in Apple Maps, or when searching for actions in Shortcuts, but it's used quite often. A panel with a small handle to pull or push it up and down on the screen. Want to implement something similar? This library from Shin Yamamoto has you covered.
There's also a similar project from Antonio Casero, Panels which is also worth a look.