Too Long; Didn't Read
React Native or RN is an open-source framework that allows you to build apps on multiple platforms like iOS or Android and web applications, using the very same code base. With React Native, you can develop mobile applications using JavaScript. The speed of work on React Native is not so great, so this technology is not very suitable for high-performance applications. It is mostly not very fast, since such code cannot always be much optimized, and it all very much depends on how you set up the project.