RxSwift is a library for composing asynchronous and event-based code by using observable sequences and functional style operators, allowing for parameterized execution via schedulers. RxSwift in its essence simplifies developing asynchronous programs by allowing code to react to new data and process it in a sequential and isolated manner.
It may seem intimidating to understand the concepts behind reactive programming at first but when you get familiar with reactive programming and RxSwift, it will help you to write better apps. Especially when writing asynchronous and event-based code, RxSwift will help you to maintain codebase with minimum effort.
Reactive programming has been around for a fairly long time, but its core concepts have made noticeable over last years. In this years apps became more complex and need to managing complex asynchronous UIs. On the server side, reactive systems have become a necessity.