Is this a bug report?

Yes

Have you read the Contributing Guidelines?

Yes

Environment

Environment:
OS: macOS Sierra 10.12.6
Node: 8.9.1
Yarn: Not Found
npm: 5.5.1
Watchman: 4.9.0
Xcode: Xcode 9.1 Build version 9B55
Android Studio: 2.3 AI-162.3871768

Packages: (wanted => installed)
react: 16.0.0 => 16.0.0
react-native: 0.50.3 => 0.50.3

Steps to Reproduce

(Write your steps here:)

1. react-native init MyApp
2. cd MyApp
3. npm start

Expected Behavior

1. The browser opens with my app

Actual Behavior

1. Nothing happens