Since I updated my phone to iOS 11 I have noticed that my React Native app briefly (<0.5s) flashes to white between the launch screen and the first screen of the app. Thi
you may start to see a white screen flash between your splash screen and the display of your root application view. try this
set your launch screen as RCTRootView loading view
AppDelegate.m
// Place this code after "[self.window makeKeyAndVisible]" and before "return YES;"
UIView* launchScreenView = [[[NSBundle mainBundle] loadNibNamed:@"LaunchScreen" owner:self options:nil] objectAtIndex:0];
launchScreenView.frame = self.window.bounds;
rootView.loadingView = launchScreenView;
More info
https://facebook.github.io/react-native/docs/running-on-device#pro-tip