Flipper is a mobile app debugger for iOS, Android, and React Native applications. From its desktop interface, developers are able to visualize, inspect, and control their mobile apps. 

It also includes functionality to enable developers to extend the platform by creating their own plugins. 

According to the project’s website, these plugins are the heart of the platform. Its documentation explains that Flipper itself is an architectural platform, but what makes it useful are the plugins. 

While users can create their own, it also comes with a few built-in plugins, such as a log viewer, interactive layout inspector, and network inspector. 

Flipper’s website includes a tutorial on how to build a plugin, which may be a good starting point for using the platform. 

Flipper was created at Facebook, and was previously known as Sonar.  

More information can be found on the project’s GitHub page, or on its website