isIPhoneX.js

import { Dimensions } from 'react-native';

// See https://mydevice.io/devices/ for device dimensions
const X_WIDTH = 375;
const X_HEIGHT = 812;

export const isIPhoneX = () => {
  const { height: D_HEIGHT, width: D_WIDTH } = Dimensions.get('window');

  return Platform.OS === 'ios' &&
    ((D_HEIGHT === X_HEIGHT && D_WIDTH === X_WIDTH) ||
      (D_HEIGHT === X_WIDTH && D_WIDTH === X_HEIGHT));
}