I have been using this IDE lately: Deco for ReactNative Dev.
It includes and auto-install components while also keeping package.json updated
After installing Deco, add the repo to the project view
Hit the Simulator button, select an iOS device, and voila
Troubleshooting & notes
Unexpected Character in whatever.png - you'll have to restart the packager. If it's running via terminal, kill the process and restart it. If it's running via Deco, kill Deco and restart. If it doesn't work, restart your computer
When installing new packages via yarn or npm, be sure to run react-native link to link the dependencies to the Xcode build. This is especially necessary with external fonts and iconography as these can break the build.