FAILURE: Build failed with an exception. * What went wrong: Execution failed for task ‘:app:installDebug’. > com.android.builder.testing.api.DeviceException: com.android.ddmlib.InstallException: Failed to establish session * Try: Run with –stacktrace option to get the stack trace. Run with –info or –debug option to get more log output

Could not install the app on the device, read the error above for details.

Make sure you have an Android emulator running or a device connected and have

set up your Android development environment:

https://facebook.github.io/React-native/docs/android-setup.html

解决方法

http://blog.csdn.net/zhangatle/article/details/53289471