Build and publish to the Play Store

You will take an Expo app from your laptop to the Google Play Store: set the app's identity, build an installable file with EAS Build, test it on a real phone, create a Play Console listing, and release it. Android is the focus, in line with the rest of this track.

Prerequisites: a working Expo app, a free Expo account (sign up at expo.dev), and a Google account. Be ready for some waiting: the first release on a new personal Play account takes days to weeks, mostly because of Google's testing rules explained below.

Rules and fees change. This lesson describes how the process works; check the official Play Console help pages for current fees and requirements.

Your app's identity lives in app.json (or app.config.js). The important fields are the name users see, the slug, the version, and the Android package name: a unique id like com.yourname.expensetracker. Once you publish with a package name, you can never change it, so choose carefully. Use reverse-domain style, lowercase, and a name you own (for example your own name or a domain you control).

{
  "expo": {
    "name": "Expense Tracker",
    "slug": "expense-tracker",
    "version": "1.0.0",
    "orientation": "portrait",
    "icon": "./assets/icon.png",
    "android": {
      "package": "com.yourname.expensetracker",
      "versionCode": 1,
      "adaptiveIcon": {
        "foregroundImage": "./assets/adaptive-icon.png",
        "backgroundColor": "#ffffff"
      }
    }
  }
}

Replace yourname with your own identifier. Keep your existing fields; only add or change these.

Your icon should be a 1024 by 1024 PNG. The adaptive icon foreground needs the artwork inside the central safe area, because Android crops it into circles, squares and other shapes on different phones. Check the Expo documentation on app icons for exact sizes.

EAS (Expo Application Services) builds your app in the cloud, so you do not need Android Studio installed or a powerful computer. EAS Build has a free plan with limits on how many builds you can do; check expo.dev pricing for the current limits, and paid plans exist for more.

npm install -g eas-cli
eas login
eas build:configure

eas build:configure creates eas.json in your project. Use npx eas-cli instead of the global install if you prefer.

Open eas.json. Add a preview profile that builds an APK, a file you can install directly on a phone. The production profile builds an AAB (Android App Bundle), the format Google Play requires for new apps.

{
  "cli": { "version": ">= 5.0.0", "appVersionSource": "remote" },
  "build": {
    "preview": {
      "distribution": "internal",
      "android": { "buildType": "apk" }
    },
    "production": {
      "autoIncrement": true
    }
  },
  "submit": {
    "production": {}
  }
}

The cli.version number may differ in your generated file; keep what eas build:configure wrote and add the profiles.

eas build --platform android --profile preview

The first time, EAS asks to generate an Android keystore. Say yes and let EAS store it.

The first build asks to create a keystore, the signing key that proves updates come from you. EAS stores it for you. If you lose a keystore you may not be able to update your app, so do not delete it from your EAS project. You can download a backup with eas credentials.

When the build finishes (often 10 to 20 minutes, longer in busy times), the terminal prints a link and a QR code. Open the link on your Android phone, download the APK and install it. Android may ask you to allow installs from your browser.

Go to play.google.com/console and sign up. You pay a one-time registration fee (at the time of writing it was about US dollars 25, charged once, not yearly; confirm on the sign-up page) using a card that works for international payments. Google also verifies your identity, which can take a few days.

You choose between a personal and an organization account. Organization accounts need a business identity (such as a D-U-N-S number) and are what companies use. A student or hobby developer normally uses a personal account.

eas build --platform android --profile production

Produces an .aab file on EAS. Download it from the build page.

The data safety form asks what data your app collects (email, location, purchases) and whether it is shared. Answer honestly and match what the app really does, because mismatches can lead to rejection or removal. If your app collects any personal data, you need a privacy policy hosted on a public URL. In India this also connects to the DPDP Act, so state clearly what you collect and why. A free page on GitHub Pages or Notion can host a simple policy.

Once the first release is uploaded manually, you can send later builds with eas submit. It needs a Google service account key (a JSON file) with permission on your Play Console app. The Expo docs ("Submit to Google Play Store") walk through creating it. Keep that JSON file out of Git.

eas build --platform android --profile production --auto-submit
# or submit the latest build later:
eas submit --platform android --profile production

In eas.json, the submit profile can point to the key file with serviceAccountKeyPath, and choose a track such as internal.

For code-only changes (JavaScript and assets), EAS Update can send an over-the-air update without a new Play review. It needs the expo-updates library set up; see the EAS Update docs. Changes to native code, new permissions or new native libraries need a new build and a new Play release with a higher versionCode. Play policies still apply to what you change through updates.

Questions include "What is the difference between APK and AAB?" (APK installs directly; AAB is the publishing format Play uses to create optimised APKs per device), "What is a keystore and why is it important?" and "How do you ship an urgent fix?" (EAS Update for JavaScript-only fixes, or a new build with a higher versionCode). Having a real published or tested app on your resume makes these answers credible.