Devtools "React" Tab Does Not Work
It's currently not possible to use the "React" tab in the devtools to inspect app widgets. This is due to a change in how the application scripts are evaluated in the devtools plugin; they are now run inside a Web Worker, and the plugin is unaware of this and so unable to communicate properly with React Native.
However, you can still use the Console feature of the devtools, and debugging JavaScript with breakpoints works too. To use the console, make sure to