Appcompat vs. AndroidX: Which Should You Use?Android development has evolved significantly over the years, and two terms you’ll frequently encounter are Appcompat and AndroidX. Choosing between them (or understanding how they relate) matters for app compatibility, access to the latest components, and long-term maintainability. This article explains what each is, how they differ, why the migration matters, and practical guidance for choosing and migrating.
What is Appcompat?
Appcompat (formally the Android Support Library’s AppCompat) is a compatibility library that provides backward-compatible implementations of Android UI components and behaviors. It was introduced to help developers use newer platform features while supporting older Android versions.
Key purposes:
- Provide consistent look-and-feel across Android versions (e.g., Material components and themes).
- Offer backward-compatible versions of components like Toolbar, ActionBar, Fragment, and many widget improvements.
- Allow developers to adopt newer APIs without dropping support for older OS releases.
Historically, Appcompat lived inside the Android Support Libraries (com.android.support:appcompat-v7 and similar artifacts).
What is AndroidX?
AndroidX (short for Android Extensions) is the successor to the Support Library. It reorganizes, renames, and improves those libraries with clearer package names and artifact coordinates. AndroidX is maintained under the androidx.* namespace (for example, androidx.appcompat:appcompat).
Key improvements over the old Support Libraries:
- Stable, consistent package naming (androidx.*) avoiding versioned artifact names like v7 or v4.
- Independent artifact modules that can be updated more frequently.
- Clearer migration path and modernized development practices.
- Better support for Jetpack libraries (Lifecycle, ViewModel, Room, WorkManager, etc.).
AndroidX is part of Android Jetpack — a set of libraries, tools, and guidance to accelerate Android development.
Relationship between Appcompat and AndroidX
These aren’t two competing products; rather, Appcompat was a component within the Support Libraries and was migrated into AndroidX. Today, when people say “Appcompat” they often mean the AppCompat library available under AndroidX, i.e., androidx.appcompat:appcompat.
- Old Support Library: com.android.support:appcompat-v7
- AndroidX: androidx.appcompat:appcompat
So choosing “Appcompat vs. AndroidX” is somewhat a historical comparison: AndroidX is the modern namespace and distribution for Appcompat and other support libraries.
Why migrate to AndroidX?
- Access to new features and bug fixes: New releases are published in AndroidX.
- Interoperability with Jetpack: Most modern libraries and architecture components require AndroidX.
- Cleaner package names and artifacts: Easier dependency management and clearer imports.
- Future-proofing: Support Library is deprecated; AndroidX is actively maintained.
Google provided an automated migration tool in Android Studio to help convert projects from the Support Library to AndroidX.
Compatibility and API differences
- Functionality remains largely the same after migration, but package/class names change (e.g., android.support.v7.app.AppCompatActivity → androidx.appcompat.app.AppCompatActivity).
- Some APIs were improved or refactored; consult release notes when upgrading major versions.
- If you use third-party libraries that still use the old Support Libraries, you may encounter conflicts. Gradle offers a compatibility artifact (jetifier) to translate binaries at build time, but it’s better when all dependencies adopt AndroidX.
Pros and Cons (comparison)
| Topic | Old Support Library (Appcompat) | AndroidX (modern Appcompat) |
|---|---|---|
| Package naming | com.android.support.* (versioned) | androidx.* (stable, clear) |
| Maintenance | Deprecated | Actively maintained |
| Jetpack interoperability | Limited | Full compatibility |
| Updates frequency | Slower, tied to platform | Faster, modular releases |
| Migration effort | N/A (legacy) | Requires migration for older projects but supported by tooling |
When to keep old Support Libraries?
Short answer: generally don’t. However, a few scenarios may delay migration:
- Legacy large codebases where migration risk is high and resources are limited.
- Some very old third-party libraries that haven’t been updated and break with jetifier.
- Projects frozen in maintenance mode with no need for new features or updates.
Even in these cases, consider planning migration because dependency support and security updates will favor AndroidX.
How to migrate: practical steps
- Update Android Studio to the latest stable version.
- Back up your project (or use version control).
- In Gradle properties, enable:
- android.useAndroidX=true
- android.enableJetifier=true
- Use Android Studio: Refactor → Migrate to AndroidX. Review the changes and run tests.
- Replace any remaining com.android.support imports/usages with androidx.* equivalents.
- Update third-party libraries to AndroidX-compatible versions where possible.
- Run full test suite and manual QA to catch runtime issues.
Notes:
- Jetifier rewrites old binary dependencies to AndroidX at build time. It’s a stopgap and may increase build time.
- After migrating, prefer adding AndroidX artifacts directly rather than relying on jetifier.
Best practices after migrating
- Use androidx.appcompat:appcompat and other AndroidX artifacts explicitly in your build.gradle.
- Keep libraries updated via dependency management tools.
- Embrace Jetpack components for architecture (ViewModel, LiveData, Navigation, WorkManager).
- Run static analysis (Lint) and unit/UI tests to validate behavior.
- Migrate third-party modules or fork/patch them if necessary.
Quick decision guide
- New projects: Use AndroidX (androidx.appcompat) from the start.
- Active projects needing updates/new features: Migrate to AndroidX.
- Legacy projects in critical maintenance mode with no resource to migrate: postpone but plan migration within roadmap.
Example: common class name changes
- android.support.v7.app.AppCompatActivity → androidx.appcompat.app.AppCompatActivity
- android.support.design.widget.FloatingActionButton → com.google.android.material.floatingactionbutton.FloatingActionButton (Material components now live under com.google.android.material)
- android.support.v4.app.Fragment → androidx.fragment.app.Fragment
Conclusion
AndroidX is the modern, actively maintained successor to the Support Libraries (including Appcompat). For nearly all cases—new projects and actively maintained apps—you should use AndroidX (androidx.appcompat:appcompat). Migration is straightforward with Android Studio tooling and unlocks better compatibility with Jetpack and newer Android features. If you must stay on the older Support Libraries, treat that as a temporary measure and plan migration soon.
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