Mastering App Versioning and Build Numbers in Flutter

9.1.2 App Versioning and Build Numbers

In the fast-paced world of mobile app development, managing updates and ensuring compatibility across different versions of your app is crucial. This is where app versioning and build numbers come into play. In this section, we’ll delve into the importance of app versioning, explore the principles of semantic versioning, and provide practical guidance on setting and incrementing version numbers in Flutter. We’ll also discuss best practices and tools to automate the versioning process, ensuring your app remains consistent and reliable across platforms.

Understanding Versioning

App versioning is a fundamental aspect of software development that helps developers manage updates, track changes, and ensure compatibility between different versions of an application. It serves as a communication tool between developers, users, and app stores, indicating the state and progression of the app.

Importance of App Versioning

• User Communication: Version numbers inform users about the updates and changes in the app. A new version number often signifies new features, bug fixes, or improvements.
• Compatibility Management: Versioning helps manage compatibility between different versions of the app and the underlying operating system or hardware.
• Update Management: It allows developers to track and manage updates efficiently, ensuring that users receive the latest features and fixes.

Version Name vs. Build Number

In Flutter, as in many other frameworks, there are two key components to versioning: the version name and the build number.

• Version Name (version): This is a human-readable string that indicates the release version of the app. It typically follows the format MAJOR.MINOR.PATCH.
• Build Number (build): This is an integer that represents the build version of the app. It is used internally by the app stores to track updates and ensure that users receive the latest version.

Semantic Versioning

Semantic Versioning (SemVer) is a widely adopted versioning scheme that provides a clear and consistent way to communicate changes in your software. It uses a three-part version number: MAJOR.MINOR.PATCH.

SemVer Principles

• MAJOR: Incremented for incompatible API changes. When you make changes that break backward compatibility, you should increase the major version number.
• MINOR: Incremented for backward-compatible functionality. When you add new features that are backward-compatible, you should increase the minor version number.
• PATCH: Incremented for backward-compatible bug fixes. When you fix bugs without introducing new features or breaking changes, you should increase the patch version number.

By adhering to semantic versioning, you provide a clear and predictable versioning scheme that helps users and developers understand the nature of changes in each release.

Setting Version and Build Number in Flutter

In Flutter, versioning is managed through the pubspec.yaml file. This file contains metadata about your app, including its version number and build number.

Configuring Version and Build Number

To set the version and build number in Flutter, you need to modify the pubspec.yaml file. Here’s an example configuration:

version: 1.0.0+1

• 1.0.0 is the version number, following the MAJOR.MINOR.PATCH format.
• +1 is the build number, which is an integer that should be incremented with each release.

Platform-Specific Considerations

Each platform (Android and iOS) uses these numbers differently:

• Android:

  • Version Name: Corresponds to the version in pubspec.yaml.
  • Version Code: Corresponds to the build number. It must be incremented with each release to ensure that users receive updates.

• iOS:

  • CFBundleShortVersionString: Corresponds to the version in pubspec.yaml.
  • CFBundleVersion: Corresponds to the build number. It must be incremented with each release.

Incrementing Version and Build Numbers

Incrementing version and build numbers is a critical part of the release process. It ensures that users receive the latest updates and that the app stores can track and manage different versions of your app.

Guidelines for Incrementing

• MAJOR: Increase when making incompatible API changes. This signals to users and developers that significant changes have been made.
• MINOR: Increase when adding functionality in a backward-compatible manner. This indicates new features or improvements that don’t break existing functionality.
• PATCH: Increase when making backward-compatible bug fixes. This communicates that bugs have been fixed without introducing new features or breaking changes.
• Build Number: Always increment the build number with each release to the app stores. This ensures that the app stores can track and manage updates effectively.

Automatic Versioning

Manually managing version numbers can be error-prone and time-consuming, especially in large projects with frequent releases. Fortunately, there are tools and scripts that can automate the versioning process.

Tools and Scripts for Automation

• Git Tags: Use Git tags to manage versions. By tagging releases in your Git repository, you can automate the versioning process and ensure consistency across your development workflow.
• CI/CD Pipelines: Integrate versioning into your continuous integration and continuous deployment (CI/CD) pipelines. This allows you to automatically increment version numbers and build numbers as part of your release process.
• Packages like flutter_version: Use packages like flutter_version to manage version numbers programmatically. These tools can automate the process of incrementing version numbers and updating the pubspec.yaml file.

Best Practices

To ensure a smooth and consistent versioning process, it’s important to follow best practices:

• Consistency Across Platforms: Keep versioning consistent across Android and iOS to avoid confusion and ensure compatibility.
• Document Changes: Maintain a CHANGELOG.md file to document version changes. This provides a clear record of what has changed in each version and helps users and developers understand the progression of your app.
• Update Before Release: Ensure that the version and build numbers are updated before building release versions. This prevents issues with app store submissions and ensures that users receive the latest updates.

Practice Exercises

To reinforce your understanding of app versioning and build numbers, try the following exercises:

1. Simulate Releasing Updates:

   • Increment the version numbers in your pubspec.yaml file.
   • Build and run your app to observe the effects of the version changes.

2. Create a Simple Changelog:

   • Document hypothetical changes in each version of your app.
   • Use the CHANGELOG.md file to track these changes and practice maintaining a clear record of your app’s progression.

By mastering app versioning and build numbers, you’ll be well-equipped to manage updates, ensure compatibility, and maintain a reliable and consistent app across platforms.

Quiz Time!