TL;DR

AndroidManifest.xml describes essential information about an app to the Android build tools

Explanation

What a AndroidManifest.xml looks like

<manifest xmlns:android="http://schemas.android.com/apk/res/android"
  package="com.voting_frontend">

    <uses-permission android:name="android.permission.INTERNET" />

    <application
      android:name=".MainApplication"
      android:label="@string/app_name"
      android:icon="@mipmap/ic_launcher"
      android:roundIcon="@mipmap/ic_launcher"
      android:allowBackup="false"
      android:usesCleartextTraffic="true"
      android:theme="@style/AppTheme">
      <activity
        android:name=".MainActivity"
        android:label="@string/app_name"
        android:configChanges="keyboard|keyboardHidden|orientation|screenSize"
        android:windowSoftInputMode="adjustResize">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
      </activity>
      <activity android:name="com.facebook.react.devsupport.DevSettingsActivity" />
    </application>

</manifest>

1. package="com.voting_frontend" is the app’s package name. The Android build tools use this to tdetermine the location of code when building an Android project. When packaging the app, the build tools replace this package name with the application ID from the Gradle build files. Google Play Store cannot publish two different apps with a same package name.

   • The Android build tools use the app name to create a R.java class like com.voting_frontend.R
   • The package name is also used for .MainActivity like com.voting_frontend.MainActivity
   • so if you change the package name, it will throw off Android build tools when creating the APK
   • The package value is replaced with the applicationId value in android/app/build.gradle

2. Components like activitiy, service, broadcast receiver, and content provider. Each component must define basic properties such as the name of its Kotlin or Java class. The above example defines MainApplication.java and MainActivity.java

3. The permissions that the app needs in order to access protected parts of the system

4. The hardware and software features the app requires