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name mobile-e2e-testing
description Set up end-to-end testing for React Native/Expo or Flutter apps. Covers Detox, Maestro, Patrol, device farm integration, CI pipeline setup, and flaky test mitigation. Use when the user wants automated tests that run on a real device or emulator and verify full user flows.
standards-version 1.9.0

Mobile E2E Testing

Trigger

Use this skill when the user:

  • Wants automated tests that tap buttons, fill forms, and verify screens on a device or emulator
  • Asks about Detox, Maestro, or Patrol
  • Needs to test full user flows like onboarding, login, or checkout
  • Mentions "end-to-end", "e2e", "integration test on device", "device farm", or "UI automation"
  • Wants to run automated tests in CI against real devices

Required Inputs

  • Framework: Expo (React Native) or Flutter
  • E2E tool: Detox, Maestro (recommended for ease of use), or Patrol (Flutter)
  • Target platform: iOS, Android, or both

Workflow

  1. Choose an E2E framework. Each has trade-offs:

    Tool Framework Language CI difficulty Flaky risk Best for
    Maestro RN + Flutter YAML flows Low Low Quick setup, readable flows
    Detox React Native JS/TS Medium Medium Deep RN integration, gray-box
    Patrol Flutter Dart Medium Low Native interaction in Flutter

    Maestro is the fastest to set up and works across both frameworks. Detox provides deeper control for React Native. Patrol extends flutter_test with native OS interaction.

  2. Set up Maestro (recommended). Install the CLI:

    # macOS
brew install maestro

# Windows / Linux
curl -Ls "https://get.maestro.mobile.dev" | bash

    Create a flow file at e2e/login.yaml:

    appId: com.yourapp
---
- launchApp
- tapOn: "Email"
- inputText: "test@example.com"
- tapOn: "Password"
- inputText: "password123"
- tapOn: "Sign In"
- assertVisible: "Welcome"

    Run it:

    maestro test e2e/login.yaml

  3. Set up Detox (React Native). Install Detox and its Jest adapter:

    npm install --save-dev detox @types/detox jest-circus
npx detox init

    Configure .detoxrc.js:

    module.exports = {
  testRunner: {
    args: { $0: "jest", config: "e2e/jest.config.js" },
    jest: { setupTimeout: 120000 },
  },
  apps: {
    "ios.debug": {
      type: "ios.app",
      binaryPath: "ios/build/Build/Products/Debug-iphonesimulator/YourApp.app",
      build: "xcodebuild -workspace ios/YourApp.xcworkspace -scheme YourApp -configuration Debug -sdk iphonesimulator -derivedDataPath ios/build",
    },
    "android.debug": {
      type: "android.apk",
      binaryPath: "android/app/build/outputs/apk/debug/app-debug.apk",
      build: "cd android && ./gradlew assembleDebug assembleAndroidTest -DtestBuildType=debug",
    },
  },
  devices: {
    simulator: { type: "ios.simulator", device: { type: "iPhone 15" } },
    emulator: { type: "android.emulator", device: { avdName: "Pixel_7" } },
  },
  configurations: {
    "ios.sim.debug": { device: "simulator", app: "ios.debug" },
    "android.emu.debug": { device: "emulator", app: "android.debug" },
  },
};

    Write a test in e2e/login.test.ts:

    describe("Login", () => {
  beforeAll(async () => {
    await device.launchApp();
  });

  it("signs in with valid credentials", async () => {
    await element(by.id("email-input")).typeText("test@example.com");
    await element(by.id("password-input")).typeText("password123");
    await element(by.id("sign-in-button")).tap();
    await expect(element(by.text("Welcome"))).toBeVisible();
  });
});

    Run Detox:

    npx detox build --configuration ios.sim.debug
npx detox test --configuration ios.sim.debug

  4. Set up Patrol (Flutter). Add the dependency:

    dev_dependencies:
  patrol: ^3.13.0
  patrol_finders: ^2.4.0

    Create integration_test/login_test.dart:

    import 'package:patrol/patrol.dart';
import 'package:my_app/main.dart' as app;

void main() {
  patrolTest('signs in with valid credentials', ($) async {
    app.main();
    await $.pumpAndSettle();

    await $(#emailInput).enterText('test@example.com');
    await $(#passwordInput).enterText('password123');
    await $(#signInButton).tap();
    await $.pumpAndSettle();

    expect($('Welcome'), findsOneWidget);
  });
}

    Run it:

    patrol test --target integration_test/login_test.dart

  5. Add testIDs for reliable selectors. In React Native, set testID props:

    <TextInput testID="email-input" />
<Pressable testID="sign-in-button">
  <Text>Sign In</Text>
</Pressable>

    In Flutter, use Key values:

    TextField(key: const Key('emailInput'))

  6. Run E2E tests in CI. For Maestro with GitHub Actions:

    - name: Run E2E tests
  uses: mobile-dev-inc/action-maestro-cloud@v1
  with:
    api-key: ${{ secrets.MAESTRO_CLOUD_KEY }}
    app-file: app-release.apk

    For Detox, run on a macOS runner with a simulator:

    jobs:
  e2e:
    runs-on: macos-latest
    steps:
    - uses: actions/checkout@v4
    - run: npm ci
    - run: npx detox build --configuration ios.sim.debug
    - run: npx detox test --configuration ios.sim.debug --cleanup

  7. Use a device farm for broader coverage. Test on real devices across OS versions:

    Service Pricing Integration
    Maestro Cloud Free tier available maestro cloud CLI
    BrowserStack App Automate Pay per minute REST API or SDK
    AWS Device Farm Pay per minute AWS CLI
    Firebase Test Lab Free Spark tier gcloud firebase test

Key References

Example Interaction

User: "I want to add E2E tests for my login and checkout flows in my Expo app."

Agent:

  1. Recommends Maestro for quick YAML-based flows
  2. Installs Maestro CLI
  3. Creates e2e/login.yaml with tap, input, and assert steps
  4. Creates e2e/checkout.yaml covering product selection through payment confirmation
  5. Adds testID props to key interactive elements in the login and checkout screens
  6. Runs maestro test e2e/ to validate both flows pass
  7. Generates a GitHub Actions workflow step for Maestro Cloud with mobile_setupCI
  8. Suggests adding the flows to PR checks for regression detection

MCP Usage

Step MCP Tool Description
Generate CI workflow mobile_setupCI Create GitHub Actions workflow with E2E test step
Run unit tests first mobile_runTests Verify unit tests pass before running slower E2E tests
Install dependencies mobile_installDependency Install detox, patrol, or related packages
Check build health mobile_checkBuildHealth Ensure the app builds before running E2E tests

Common Pitfalls

  1. Missing testIDs - E2E tests that rely on text selectors break when copy changes. Use testID (RN) or Key (Flutter) for stable selectors.
  2. Not waiting for animations - Tapping during transitions causes flaky failures. Use waitForVisible (Maestro), waitFor (Detox), or pumpAndSettle (Patrol).
  3. Hardcoded test data - Tests that depend on specific server state fail when the backend changes. Use test accounts, seed data, or mock APIs.
  4. Running E2E on every commit - E2E tests are slow (minutes). Run them on PRs targeting main or on a nightly schedule, not on every push.
  5. Ignoring flaky tests - A flaky test erodes trust in the suite. Fix or quarantine flaky tests immediately. Add retry logic only as a last resort.
  6. Detox requires a dev build - Detox does not work with Expo Go. Use npx expo prebuild or EAS Build to create a dev client first.

See Also