React Native: Build apk file using Expo CLI

Question

I'm a new learner on this platform.
I code a simple react native app using expo. But I want to build a .apk file.
I tried this command:

expo build:android

Then I sign up an expo account. After completing the building process it shows the download button.
Just like the following picture: But its not apk file. It is .aab file.
So, I want to build an actual apk file.
How can I do that?

Answer 1

to build a apk out of the file first you need to do some changes to your eas.json file.

By default, EAS Build produces Android App Bundle, you can change it by:

• setting buildType to apk
• setting developmentClient to true
• setting gradleCommand to :app:assembleRelease, :app:assembleDebug or any othergradle command that produces APK

after changing the config you can run eas build -p android --profile preview to build the application

you can read more about this in docs https://docs.expo.dev/build-reference/apk/

and here's a sample config i used for a basic project to build ( also you can find on docs )

{
  "cli": {
    "version": ">= 0.52.0"
  },
  "build": {
    "preview": {
      "android": {
        "buildType": "apk"
      }
    },
    "preview2": {
      "android": {
        "gradleCommand": ":app:assembleRelease"
      }
    },
    "preview3": {
      "developmentClient": true
    },
    "production": {}
  }
}

--

also alternatively another possible way would be to get the bundle ( .aab ) file and convert it to apk using a too like bundletool. and you can find the apk ( universal.apk ) inside app.apks

bundletool build-apks --bundle=bundle.aab --output=app.apks --mode=universal 

https://github.com/google/bundletool

Answer 2

By default Expo, CLI builds the app into a .aab file format. this format is better for Google Play Store as it will be optimized for every device CPU architecture which results in a smaller app size.

In case you want to test for your device or emulator, run:
expo build:android -t apk