Preparing a release

Release versus debug

During development you run debug builds: slower, with hot reload, debug banners and extra checks. Users get release builds: compiled ahead of time to fast native code, smaller, and without debugging tools. Before your first release there is a checklist of things to set up once.

Identity: application ID and bundle ID

Every app has a unique identifier on each platform. On Android it is the applicationId (in android/app/build.gradle or build.gradle.kts), like com.sharmasweets.orders. On iOS it is the bundle identifier, set in Xcode. flutter create uses com.example.app_name; never publish with com.example. Choose your final IDs before the first upload, because they cannot be changed afterwards: a new ID means a new app.

Name, icon and splash

• Display name: android:label in AndroidManifest.xml and CFBundleDisplayName in ios/Runner/Info.plist.
• Launcher icons: each platform needs many sizes; the flutter_launcher_icons package generates them from one 1024 x 1024 image, including Android adaptive icons.
• Splash screen: Android 12+ has a system splash API and iOS uses a launch screen; the flutter_native_splash package configures both from pubspec settings.

Versioning

version: 1.4.2+23

Flutter maps this to Android's versionName (1.4.2) and versionCode (23), and to iOS's CFBundleShortVersionString and CFBundleVersion. The build number must be higher than every build you uploaded before, or the stores reject the upload. A common habit: bump the version name for each release following MAJOR.MINOR.PATCH and increase the build number for every upload, even test builds.

flutter build appbundle --build-name=1.4.3 --build-number=24

Obfuscation

Obfuscation renames classes and functions in the compiled code to meaningless names, making reverse engineering harder (not impossible). Flutter supports it for Android and iOS release builds. --split-debug-info stores the symbol files needed to read crash stack traces; keep them, or crash reports become unreadable.

flutter build appbundle --obfuscate --split-debug-info=build/symbols
flutter build ipa --obfuscate --split-debug-info=build/symbols

Final checklist

• Remove print statements with personal data, test buttons and debug-only shortcuts.
• Point the app at production APIs, not your test server (use build flavors or --dart-define for environments).
• Test the release build on real devices: flutter run --release.
• Publish a privacy policy page if you collect any personal data (stores require a URL).
• Check permissions: request only what you need, with clear explanations.

Common mistakes

• Publishing with the default com.example ID: rejected by stores, and changing it later creates a new app.
• Forgetting to increase the build number: "Version code has already been used".
• Losing the --split-debug-info symbols: unreadable crash reports.
• Testing only debug builds: release-only problems (like a missing INTERNET permission) reach users.