Read app.json (or exp.json) programmatically

For expo SDK 33 use:

 import Constants from "expo-constants";
 {`v${Constants.manifest.version}`}

You can access this through Constants.manifest. This includes your app.json config without any of the potentially sensitive information such as API secret keys.

import Constants from 'expo-constants';
Constants.manifest.version 

For Expo SDK 35, I did this:

expo install expo-constants

in your .js:

import Constants from "expo-constants";

<Text> {Constants.manifest.description} </Text>

Newer versions of expo (I'm on 36) now import the variable differently

import Constants from 'expo-constants';

Read all about it here on the expo documentation site