react-native-navigation/example/ios/example/AppDelegate.m

#import "AppDelegate.h"
#import <React/RCTBundleURLProvider.h>

// **********************************************
// *** DON'T MISS: THE NEXT LINE IS IMPORTANT ***
// **********************************************
#import "RCCManager.h"

// IMPORTANT: if you're getting an Xcode error that RCCManager.h isn't found, you've probably ran "npm install"
// with npm ver 2. You'll need to "npm install" with npm 3 (see https://github.com/wix/react-native-navigation/issues/1)

#import <React/RCTRootView.h>

@implementation AppDelegate

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
  NSURL *jsCodeLocation;
#ifdef DEBUG
//  jsCodeLocation = [NSURL URLWithString:@"http://localhost:8081/index.ios.bundle?platform=ios&dev=true"];
  jsCodeLocation = [[RCTBundleURLProvider sharedSettings] jsBundleURLForBundleRoot:@"index.ios" fallbackResource:nil];
#else
   jsCodeLocation = [[NSBundle mainBundle] URLForResource:@"main" withExtension:@"jsbundle"];
#endif


  // **********************************************
  // *** DON'T MISS: THIS IS HOW WE BOOTSTRAP *****
  // **********************************************
  self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
  self.window.backgroundColor = [UIColor whiteColor];
  [[RCCManager sharedInstance] initBridgeWithBundleURL:jsCodeLocation];

  /*
  // original RN bootstrap - remove this part
  RCTRootView *rootView = [[RCTRootView alloc] initWithBundleURL:jsCodeLocation
                                                      moduleName:@"example"
                                               initialProperties:nil
                                                   launchOptions:launchOptions];
  self.window = [[UIWindow alloc] initWithFrame:[UIScreen mainScreen].bounds];
  UIViewController *rootViewController = [UIViewController new];
  rootViewController.view = rootView;
  self.window.rootViewController = rootViewController;
  [self.window makeKeyAndVisible];
  */
  

  return YES;
}

@end