Running Mobile Tests With Expo EAS

An .ipa is meant for physical devices. A simulator run needs a simulator app bundle.

In EAS, the profile looks like this:

eas.json

{
  "build": {
    "testerarmy-ios-simulator": {
      "ios": {
        "simulator": true
      }
    }
  }
}

Once EAS produces that .app, the workflow can upload it to TesterArmy and start a saved mobile test group.

What TesterArmy handles

The EAS workflow should stay simple. It only needs to orchestrate five things:

1. Build the iOS Simulator app.
2. Download the .app artifact.
3. Upload the app to TesterArmy.
4. Run the selected mobile test group.
5. Delete the temporary app upload when the run finishes.

TesterArmy handles the rest:

• Cloud simulator provisioning
• App installation
• Agent-driven mobile test execution
• Screenshots, videos, and run artifacts
• Result polling
• GitHub checks and PR comments

That split is the whole integration. EAS gives us a build. TesterArmy runs it.

The required values

The workflow needs three values from TesterArmy.

Keep TESTERARMY_API_KEY as an EAS secret or sensitive environment variable. Do not expose it through EXPO_PUBLIC_*, and do not commit it.

The project ID and group ID are not sensitive in the same way, but keeping all three values in the EAS environment makes the workflow easier to reuse across projects.

Adding the workflow

The basic workflow has three jobs.

First, build the simulator app:

.eas/workflows/testerarmy-mobile-tests.yml

jobs:
  build_ios:
    name: Build iOS Simulator app
    type: build
    environment: preview
    params:
      platform: ios
      profile: testerarmy-ios-simulator

Next, download the EAS artifact and upload it to TesterArmy:

.eas/workflows/testerarmy-mobile-tests.yml

jobs:
  upload_app:
    name: Upload app to TesterArmy
    needs: [build_ios]
    environment: preview
    outputs:
      app_id: ${{ fromJSON(steps.upload_app.outputs.upload_result).uploadedAppId }}
    steps:
      - uses: eas/checkout

      - uses: eas/download_build
        id: download_build
        with:
          build_id: ${{ needs.build_ios.outputs.build_id }}
          extensions:
            - app

      - name: Upload app
        id: upload_app
        run: |
          set -euo pipefail

          APP_PATH="${{ steps.download_build.outputs.artifact_path }}"

          mkdir -p .testerarmy

          npx --yes testerarmy@latest upload-app \
            --app-path "$APP_PATH" \
            --project "$TESTERARMY_PROJECT_ID" \
            --output .testerarmy/upload.json

          set-output upload_result "$(tr -d '\n' < .testerarmy/upload.json)"

Finally, run the saved test group with the uploaded app ID:

.eas/workflows/testerarmy-mobile-tests.yml

jobs:
  run_tests:
    name: Run TesterArmy tests
    needs: [upload_app]
    environment: preview
    steps:
      - uses: eas/checkout

      - name: Run tests
        run: |
          set -euo pipefail

          APP_ID="${{ needs.upload_app.outputs.app_id }}"
          COMMIT_SHA="${{ github.sha }}"
          EVENT_NAME="${{ github.event_name }}"
          PR_NUMBER="${{ github.event.pull_request.number || '' }}"

          args=(
            ci
            --group "$TESTERARMY_GROUP_ID"
            --project "$TESTERARMY_PROJECT_ID"
            --app-id "$APP_ID"
            --commit-sha "$COMMIT_SHA"
            --timeout "1800000"
            --poll-interval-seconds "10"
            --output .testerarmy/ci-result.json
            --delete-app-after-run
          )

          if [ "$EVENT_NAME" = "pull_request" ] && [ -n "$PR_NUMBER" ]; then
            args+=(--pr-number "$PR_NUMBER")
          fi

          npx --yes testerarmy@latest "${args[@]}"

The full copy-paste version is in the Expo EAS docs.

Getting PR feedback

When this runs on a pull request, TesterArmy can create a GitHub check and leave a PR comment. Reviewers get the normal pass/fail signal, plus links to the run details, screenshots, videos, and logs.

To enable that, connect your TesterArmy project to the GitHub repository from the project Integrations tab.

After that, pass the commit SHA and PR number from the EAS workflow:

testerarmy ci \
  --group "$TESTERARMY_GROUP_ID" \
  --project "$TESTERARMY_PROJECT_ID" \
  --app-id "$APP_ID" \
  --commit-sha "$COMMIT_SHA" \
  --pr-number "$PR_NUMBER"

On push events, TesterArmy attaches the check to the commit. On pull requests, it can attach the check and the PR comment.

Using Expo Repack

The basic workflow runs a full simulator build every time. Start there. It is slower, but it removes a lot of variables while you are setting up the integration.

Once that is stable, you can make the workflow faster with EAS fingerprint and Expo Repack. This is useful when a pull request changes JavaScript only and the native runtime is still compatible.

The optimized workflow calculates the native runtime fingerprint, looks for a compatible simulator build, and repacks it with the current JavaScript bundle when the native layer did not change.

You still test the code from the branch, but you do not pay for a full native rebuild on every PR.

That workflow variant is included in the Expo EAS docs. Treat it as an optimization, not the first thing to debug.

Common mistakes

The most common issue is uploading the wrong artifact.

TesterArmy needs an iOS Simulator .app build. If the workflow uploads an .ipa, the run cannot install it in the simulator.

The second issue is running a group that does not contain mobile tests. Before adding EAS, run the mobile test manually from the dashboard once. Check that the app upload works, the test passes, and the test is in the group you plan to call from CI.

The third issue is missing GitHub integration. Tests still run without it, but PR comments and commit checks need the TesterArmy project to be connected to the repository.

That's a wrap

Expo EAS already knows how to build your app. TesterArmy just needs the simulator artifact.

The setup is: create an iOS Simulator build profile, add the EAS workflow, configure the three environment variables, and run the saved test group on every PR.

If you want the exact copy-paste setup, start with the Expo EAS integration docs. If you still need to create your first mobile test, start with App Uploads.