expo/src/Constants.js

The Expo SDK

// @flow

import { NativeModules } from 'react-native';

// On Android we pass the manifest in JSON form so this step is necessary
let { ExponentConstants } = NativeModules;

let manifest;
if (ExponentConstants && ExponentConstants.manifest) {
  manifest = NativeModules.ExponentConstants.manifest;
  if (typeof manifest === 'string') {
    manifest = JSON.parse(manifest);
  }
}

module.exports = {
  ...NativeModules.ExponentConstants,
  manifest,
};