Expo

Momentic tests the native build of an Expo app, not the JS bundle. The pipeline is: produce an APK (Android) or simulator .app (iOS), upload it to a channel/tag, and run momentic-mobile against it. Both EAS Build and expo prebuild with local toolchains work.

Produce a testable build

Android (APK)
iOS (simulator .app)

Option A: EAS (recommended if you already use it)

eas build --platform android --profile preview --local

A preview profile with "buildType": "apk" (or "distribution": "internal") in eas.json produces an installable .apk. Without --local, the build runs in EAS cloud and you download the artifact URL.Option B: prebuild + Gradle (no EAS account)

npx expo prebuild --platform android   # generates android/
cd android && ./gradlew assembleRelease
# APK in android/app/build/outputs/apk/release/

Momentic runs simulator builds, not device .ipa files.

npx expo prebuild --platform ios        # generates ios/
xcodebuild \
  -workspace ios/MyApp.xcworkspace \
  -scheme MyApp \
  -sdk iphonesimulator \
  -configuration Debug \
  -derivedDataPath build \
  build-for-testing
# .app in build/Build/Products/Debug-iphonesimulator/

Or with EAS, using a simulator profile:

eas build --platform ios --profile preview --local

where preview sets "ios": { "simulator": true } in eas.json.

Upload and run

Remote emulators and simulators install the app from an uploaded asset. Add the CLI as a dev dependency so the lockfile pins the version in CI:

npm install --save-dev momentic-mobile

Then upload and run:

npx momentic-mobile assets upload ./android/app/build/outputs/apk/release/app-release.apk \
  --channel dev --tag 1.0.0

Then run a test against it:

smoke.test.yaml

fileType: momentic/mobile-test/v2
id: expo-smoke
platform: android
labels: [smoke]
defaultChannel: dev
defaultTag: "1.0.0"
steps:
  - openApp: com.example.myapp
  - assert: The home screen is visible

npx momentic-mobile run smoke.test.yaml

defaultChannel/defaultTag on the test pick the uploaded asset. In the editor, the same selection appears as the Channel/Tag pickers next to the Region dropdown; choose any Momentic region for a remote instance.

Expo-specific pitfalls

Expo Go is not testable. Momentic installs your standalone build, not Expo Go. You need a prebuild or EAS artifact, and over-the-air JS updates do not reach the installed binary: rebuild when the JS surface changes (new screens, new native modules).
Dev-client builds work. An expo-dev-client build is a normal APK; test it the same way. Point it at a reachable Metro/dev server or a published update channel.
Deep links and app links resolve through the installed app id; use an appium step (mobile: deepLink) to open them.
expo-router headers and safe areas appear as native elements to Momentic: describe them as the user sees them (“the back chevron”, “the Settings tab”) rather than by testID.
WebView content on Android needs WebView.setWebContentsDebuggingEnabled(true); add it in MainApplication or a small config plugin if your app renders web content.

In CI

Run an EAS build, upload the artifact to a channel, then run your suite against that same upload. A complete GitHub Actions workflow:

.github/workflows/mobile.yml

name: Mobile tests
on: [pull_request]

jobs:
  test:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4

      - name: EAS build (Android preview)
        run:
          eas build --platform android --profile preview --local
          --non-interactive
        env:
          EXPO_TOKEN: ${{ secrets.EXPO_TOKEN }}

      - name: Upload APK to Momentic
        run: |
          npm install
          npx momentic-mobile assets upload ./*.apk \
            --channel dev --tag ${{ github.sha }}
        env:
          MOMENTIC_API_KEY: ${{ secrets.MOMENTIC_API_KEY }}

      - name: Run mobile tests
        run: |
          npx momentic-mobile run --labels smoke \
            --channel dev --tag ${{ github.sha }} -y
        env:
          MOMENTIC_API_KEY: ${{ secrets.MOMENTIC_API_KEY }}

--channel dev --tag ${{ github.sha }} selects the asset this job just uploaded; without it, tests fall back to their defaultChannel/defaultTag and can pick up a stale build.

Overview

Migrate to Momentic

Frameworks

Use cases

Triage

AI actions

Authentication

Page interactions

Test data & variants

Visual testing

Reporting

Upgrading

Produce a testable build

Upload and run

Expo-specific pitfalls

In CI

​Produce a testable build

​Upload and run

​Expo-specific pitfalls

​In CI

​Related

Produce a testable build

Upload and run

Expo-specific pitfalls

In CI

Related