Example app guesses the IP address for you. (#637)

example/ios/example/AppDelegate.m

 #import "AppDelegate.h"
+#import "RCTBundleURLProvider.h"
 
 // **********************************************
 // *** DON'T MISS: THE NEXT LINE IS IMPORTANT ***
 {
   NSURL *jsCodeLocation;
 #ifdef DEBUG
-  jsCodeLocation = [NSURL URLWithString:@"http://localhost:8081/index.ios.bundle?platform=ios&dev=true"];
+//  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