Building and Releasing Flutter Applications for Android:

Flutter, Google's mobile SDK, allows developers to build native iOS and Android, as well as desktop and web applications from a single codebase. At the core of Flutter applications are widgets - structural elements that compose the user interface and provide material design functionality. Developers combine widgets to compose user interfaces in Flutter. 


This article discusses how to build and release a Flutter application for Android devices. There are two primary release formats once an app is ready for publication to the Google Play Store:


App Bundle

The App Bundle is Google's recommended release format. To build an App Bundle from the command line:

1. Open a terminal window and navigate to the project directory 
2. Run the command "flutter build appbundle"

This will create an app bundle file at ./build/app/outputs/bundle/release/app.aab containing compiled code for different CPU architectures.

APK 

To build an APK instead:


1. Open a terminal and navigate to the project directory
2. Run "flutter build apk --split-per-abi" 





This will create three APK files at ./build/app/outputs/apk/release/ for armeabi-v7a, arm64-v8a, and x86_64 architectures.


Installing on a Device

To install the release APK on a connected Android device:


1. Connect the Android device to the computer via USB
2. Navigate to the project directory 
3. Run "flutter install"