How to Export an APK from VULK

Updated July 17, 2026 — refreshed with AAB export, current plan requirements, and verified platform data.

How do you export an APK from VULK?

The complete answer: open your Flutter project in the VULK editor, verify it runs cleanly in the preview, then click Export APK in the toolbar. VULK resolves your pubspec.yaml dependencies, compiles your Dart code ahead-of-time to native ARM machine code, bundles assets, assembles and signs the APK — typically in 30 to 90 seconds — and gives you a .apk you can install on any Android device. AAB export (the format Google Play requires) is available the same way.

This is the step most AI app builders cannot do: they generate mobile code, but you have to set up a local toolchain to get a binary. On VULK, Flutter is the #2 platform (5.6% of projects with a detectable stack) and the most requested platform in prompts (VULK platform data, July 2026) — and prompt-to-installable-APK is the reason.

What do you need before exporting?

Before exporting, make sure your project meets these requirements:

• The project must be a Flutter project. APK export builds Flutter apps. If you are unsure, check the file tree -- Flutter projects have a lib/ directory with .dart files and a pubspec.yaml.
• The app must compile in the preview. If the preview shows errors, the APK build will fail too. Fix any compilation issues first by asking VULK to resolve them in the chat.
• You need a plan with export. APK/AAB export is available on Builder, Pro, Team, Max, and Business plans.

Step 1: How do you verify the app in the preview?

Open your Flutter project in the VULK editor. The right panel shows the preview of your app -- a real server-side flutter build web compilation of your Dart code. Navigate through every screen and test the core interactions:

• Do all navigation routes work? Tap through your bottom navigation bar, drawer menu, or tab bar.
• Do forms validate correctly? Try submitting empty fields.
• Do lists render with the expected data?
• Are there any visual glitches -- overflow errors, misaligned elements, or missing images?

Fix issues before exporting. It is much faster to iterate in the browser preview than to rebuild an APK for each fix. Use follow-up prompts like:

The profile screen has a text overflow error on long usernames. Fix it by adding overflow ellipsis and a max width constraint.

The bottom navigation bar icons are not highlighting when I switch tabs. Make sure the selectedIndex updates correctly.

Step 2: What happens when you click Export APK?

Once your app is stable in the preview, locate the Export APK button in the editor toolbar. It is in the top action bar, next to the Deploy button. Click it to start the build process.

What happens behind the scenes:

1. Dependency resolution. VULK runs the equivalent of flutter pub get to install all packages listed in your pubspec.yaml.
2. Dart compilation. Your Dart source code is compiled to native ARM machine code using Flutter's ahead-of-time (AOT) compiler. This is different from the web preview, which uses a JavaScript compilation target.
3. Resource bundling. Assets like fonts, images, and JSON files referenced in your pubspec.yaml are packaged into the APK.
4. APK assembly. The compiled code, resources, Android manifest, and Flutter engine are assembled into a single .apk file.
5. Signing. The APK is signed with a key VULK keeps for your account, or with your own keystore once you upload it in app signing settings, so it installs on any Android device without Play Store distribution and later builds install as updates.

The build typically takes 30 to 90 seconds depending on project complexity and the number of dependencies.

Step 3: How do you download the APK?

When the build completes, a download dialog appears with your .apk file. The file is named after your project -- for example, workout-tracker.apk. Click to download it to your computer.

The file size depends on your app's complexity. A typical VULK-generated Flutter APK ranges from 15 MB to 40 MB. This includes the Flutter engine (~10 MB), your compiled Dart code, and any bundled assets.

Step 4: How do you install the APK on your Android device?

There are two ways to get the APK onto your phone.

Option A: Direct transfer

1. Connect your Android device to your computer via USB.
2. Copy the .apk file to your device's Downloads folder.
3. On your phone, open a file manager app and navigate to Downloads.
4. Tap the .apk file.
5. Android will prompt you to allow installation from unknown sources (since this is not from the Play Store). Enable it for your file manager app.
6. Tap Install.

Option B: Self-transfer

1. Upload the .apk file to Google Drive, Dropbox, or send it to yourself via email or messaging app.
2. On your Android device, open the file from the cloud service or message.
3. Follow the same installation prompts as Option A.

After installation, your app appears in the app drawer like any other Android app. It has the Flutter default icon unless you specified a custom launcher icon in your prompt.

What does the exported APK contain?

• Your compiled Dart code running natively on ARM — no web view, no JavaScript bridge
• Material Design components compiled into native widgets
• Bundled assets — images, fonts, data files referenced in your project
• The Flutter engine — the C++ runtime powering the rendering pipeline

For Google Play, export an AAB (App Bundle) instead, or download the source and build a signed release locally with flutter build appbundle --release.

What are the common issues and how do you fix them?

Build fails with dependency errors

Some Flutter packages require specific SDK versions or have platform-specific dependencies that conflict. VULK pins dependency versions during generation to keep server-side builds green, but if the build fails, check the error message in the export dialog and ask:

The build failed because of a dependency conflict. Please update the http package to the latest version and make sure all dependencies are compatible.

App crashes on launch

This usually means a runtime error in your Dart code that did not surface in the web preview. Common causes include platform channel calls (trying to access a native API that works differently on Android vs web) or null reference errors in data handling. Check the preview carefully and fix any issues before re-exporting.

App looks different on phone vs preview

The web preview uses Flutter Web rendering, while the APK uses the Skia-based native renderer. Minor differences in text rendering, shadow quality, and antialiasing are expected. If the layout is significantly different, it is likely a responsive issue -- the preview iframe may be a different width than your phone screen. Add responsive checks:

Make the home screen layout adapt to different screen widths. On screens narrower than 360dp, use a single-column layout instead of the two-column grid.

APK is too large

Flutter APKs include the engine, which adds approximately 10 MB. If your app includes large assets (high-resolution images, bundled JSON datasets), the size increases. To reduce size, use network-loaded images instead of bundled assets, and consider downloading the source code to build per-architecture APKs with --split-per-abi (~8 MB for arm64).

What comes after the APK?

The exported APK is ideal for testing, demos, and sharing with stakeholders. To publish on Google Play:

1. Export an AAB from VULK — the App Bundle format Google Play requires.
2. Upload your release keystore in app signing settings if you already have one for this app; otherwise VULK signs with the key it keeps for your account.
3. Customize the app icon using the flutter_launcher_icons package.
4. Submit to Google Play Console for distribution.

You can also download the source code (ZIP export) at any time and keep building in Android Studio or VS Code.

VULK gets you from idea to working Android app in minutes -- across the platform, the median time from signup to a first generated app is 47 seconds (VULK platform data, July 2026). The APK export lets you hold that app in your hand and show it to real users. The path from there to the Play Store is a standard Flutter publishing workflow -- your code is clean, standard Dart, and ready for production tooling.