Maybe you're like me. Maybe you've been working with ReactJS for a while and you want to play with React Native.

You download all of the appropriate tools to try and get a Android "Hello World" app working.

You create your project with react-native init HelloWorld and you run it with react-native run-android and it dies.

I don't know exactly what causes ☝️ but it's easy (albeit completely non-obvious) to fix. Luckily, you only have to follow these steps with a new project.

Create the android assets directory

mkdir android/app/src/main/assets

Manually start the React packager

react-native start --reset-cache

Manually force a build of the android build

curl "https://localhost:8081/index.android.bundle?platform=android" -o "android/app/src/main/assets/index.android.bundle"

Profit!

Now you should be able to do react-native run-android to launch your app.

One more thing

If you get any errors about hot-reloading and not connecting to the development console, just run adb reserve tcp:8081 tcp:8081 and then reload the app on the device.