This might me an interview question. What are differences between build types, build variants and product flavors?

Build Type

Lets start with build types.In Android development, a “build type” is a configuration that specifies how your Android app is built and packaged during the build process. Build types allow you to define different build configurations for your app, each with its own set of settings, such as optimization, code minification, and debug information. This enables you to create different versions of your app for various purposes, such as debugging, testing, and releasing to the Google Play Store.

Common build types in Android include:

  • Debug: This build type is typically used during development and debugging. It includes debuggable code, minimal code optimization, and detailed error information. The debug build type often allows for quicker build times, making it suitable for debugging.
  • Release: The release build type is used for creating the final, production-ready version of your app. It includes optimizations like code shrinking, minification, and removal of debug information. This reduces the size of the app and makes it more efficient.
  • Staging: A staging build type is used for creating builds that are meant for testing and quality assurance. It is similar to the release build type but may have specific configurations for testing environments.
  • Custom Build Types: You can create custom build types to meet specific needs. For example, you might create a qa build type for internal quality assurance or a beta build type for testing by a limited group of users.

To configure build types in an Android project, you typically modify your app’s build.gradle file. Here’s an example of how build types are defined in the build.gradle file:

android {
    buildTypes {
        debug {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
        release {
            minifyEnabled true
            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
        }
        staging {
            // Configuration for the staging build type
        }
    }
}

Product Flavor

In Android development, “product flavors” are a mechanism that allows you to create different versions of your app with variations in features, branding, and configurations. Product flavors are typically used to build multiple versions of an app from a single codebase, each targeting a specific market segment, device type, or other criteria.

Here are some common use cases for product flavors:

  • Branding: You can create product flavors to customize the branding of your app. For example, you might have different flavors for a free version and a paid version of your app, each with a different app name, logo, or theme.
  • Server Endpoints: Product flavors are useful when your app communicates with different server endpoints. For instance, you can define flavors for development, staging, and production environments, each with its own server URLs.
  • Feature Variations: If you want to release different versions of your app with varying sets of features, product flavors can help. For example, you might have a “lite” flavor with basic features and a “premium” flavor with additional features.
  • Device Configurations: When your app needs to be customized for different device types or screen sizes, you can create product flavors for each target platform, ensuring that the app’s layout and resources are optimized for each configuration.

To configure product flavors in an Android project, you typically modify your app’s build.gradle file. Here’s an example of how product flavors are defined:

android {
    flavorDimensions "version"

    productFlavors {
        free {
            dimension "version"
            applicationId "com.example.free"
            versionCode 1
            versionName "1.0"
        }
        paid {
            dimension "version"
            applicationId "com.example.paid"
            versionCode 2
            versionName "1.0"
        }
    }
}

In this example, the build.gradle file defines two product flavors: free and paid. Each flavor has its own applicationId, versionCode, and versionName, allowing for different package names and version information.

When you build your app, you can select the product flavor you want to build, and the corresponding variant of the app will be generated with the specified configurations. This enables you to maintain a single codebase while creating multiple distinct versions of your app to cater to different audiences or use cases.

Here is an important detail to distinguish between these two;

  • buildType is the how of the build.
  • flavor is the what of the build.

Build Variant

Final math is for build variants is like:

build type * product flavor = build variants

For example, let say we have debug, qa, and prod build types for different phase of developments. And We have both free and premium product flavors. In this case we will have 6 different build variants.

  • debug - free
  • debug - premium
  • qa - free
  • qa - premium
  • prod - free
  • prod - premium