Futures and Promises are one solution developers have come up with to handle some of the problems that crop up with asynchronous programming. This post will show you how to get rid of ugly nested code and benefit from easier debugging of cleaner code.
There are frameworks that take this example further, but you'll need to understand what's going on at a basic level before using them. Great explanation!
Under the hood of Futures & Promises in Swift by John Sundell
If you have a successful iOS app, inevitably the dreaded Android question starts popping up. When this happened to me a few years ago, I explored Android a bit and decided to hire a dev to build the app. I just didn't have the energy or desire to become an Android dev. But what if I could have used my iOS code? This project is one to watch with the introduction of the beta Swift Android Toolchain.
Swift in Android Apps by John Holdsworth