React library manipulates the view layer only. It’s uncomplicated and featherweight. Unlike full-featured frameworks like Angular, React allows any JavaScript developer get on board and start using React just after reading small tutorials. React way of thinking is different than most of the developers used to, but easy to understand and implement in several days of coding.

React app consist of the building blocks which are called components. You begin with small ones like input fields, buttons, checkboxes, etc. and after that create wrappers from them. Proceeding with next level wrappers you end up having one root component that becomes your application. Every component has its own logic and that approach provides surprisingly effective results.

Modern web apps are evolving quickly, gaining performance improvements by JavaScript engines optimizations, but there are still some limitations like DOM manipulations. When you need to add a complex system for user interaction the app performance may suffer. React proposes a concept of virtual DOM to solve this issue. DOM is kept and memory which allows its fast changing. Then its states are compared and changes take effect following efficient algorithms. This allows receiving minimum r/w time and get a performance boost.

Flux architecture, introduced by Facebook, enhances React components with the unified data flow. The main principle is to create actions which are controlled by a main central dispatcher to update stores. Then the views updates respect the changes happening in those stores. It helps to avoid data duplication and keeps you away from making model data in sync inside the whole application. The most well-known implementation of Flux is the Redux library. It changes Flux a bit but introducing a single store, but you benefit from having one single object which contains all the app data.

Designing the architecture for your app does not require understanding the internal process. React provides transparent abstraction layer for the developers, effectively hiding any complimentary concepts. All you need is the understanding of the states, props and components lifecycle.

React includes additional library called React Native. It allows creating native iOS and Android mobile apps using the same approach and techniques as for web applications. It won’t be exactly the same codebase, but it will be trouble-free to adopt it. Once you master React switching to React Native is easy.

Dev tools are what should be taken into considerations when you choose a platform for your application. For React there are two major players created as Chrome browser extensions: React Developer Tools and Redux Developer Tools. These utilities allow inspecting components, their grouping and look into current states and props. When working with Redux you can observe store state and changes, dispatched actions, etc.