React IOS & Android simultaneous device development

Android

With the device connected and in development mode (Google it), port-forward :8081 on your Android device.

Then run react-native run-andoid. Done.

IOS

Open AppDelegate.m in Xcode.

Replace:

jsCodeLocation = [[RCTBundleURLProvider sharedSettings] jsBundleURLForBundleRoot:@"index.ios" fallbackResource:nil];

with

#ifdef DEBUG
  jsCodeLocation = [NSURL URLWithString:@"http://[YOUR_LOCAL_IP_HERE]:8080/index.ios.bundle?platform=ios&dev=true"];
#else
  jsCodeLocation = [[RCTBundleURLProvider sharedSettings] jsBundleURLForBundleRoot:@"index.ios" fallbackResource:nil];
#endif

Then run react-native start --port 8080. Build from Xcode to your IOS device. Done.

Notes

• Make sure you're running everything on the same Wifi network
• Shake devices to open dev menu and enable hot/live reloading
• Debug JS Remotely is shit so only use it when you reallly need to console.log something.