Mobile Testing

Testing native iOS/Android apps and mobile web. Different from web testing: platform APIs, gestures, device fragmentation, permissions, network conditions, and battery state all affect behaviour.

Mobile Testing Types

Appium

WebDriver-protocol automation for iOS and Android from one codebase. Supports Python, JS, Java.

# Python + Appium — login flow on Android
from appium import webdriver
from appium.options.android import UiAutomator2Options
from appium.webdriver.common.appiumby import AppiumBy
from selenium.webdriver.support.wait import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC

options = UiAutomator2Options()
options.platform_name = "Android"
options.device_name = "emulator-5554"
options.app = "/path/to/myapp.apk"
options.automation_name = "UiAutomator2"
options.no_reset = False

driver = webdriver.Remote("http://localhost:4723", options=options)
wait = WebDriverWait(driver, 10)

try:
    wait.until(EC.presence_of_element_located((AppiumBy.ID, "com.myapp:id/email")))
    driver.find_element(AppiumBy.ID, "com.myapp:id/email").send_keys("user@example.com")
    driver.find_element(AppiumBy.ID, "com.myapp:id/password").send_keys("password123")
    driver.find_element(AppiumBy.ID, "com.myapp:id/login_button").click()

    wait.until(EC.presence_of_element_located((AppiumBy.ID, "com.myapp:id/home_screen")))
    assert driver.find_element(AppiumBy.ID, "com.myapp:id/welcome_text").is_displayed()
finally:
    driver.quit()

XCUITest (iOS Native)

Apple's built-in framework. Runs in the same process as the app on simulator/device.

// LoginTests.swift
import XCTest

class LoginTests: XCTestCase {
    let app = XCUIApplication()

    override func setUpWithError() throws {
        continueAfterFailure = false
        app.launchArguments = ["--uitesting"]
        app.launch()
    }

    func testSuccessfulLogin() throws {
        let emailField = app.textFields["email-field"]
        XCTAssert(emailField.waitForExistence(timeout: 5))
        emailField.tap()
        emailField.typeText("user@example.com")

        app.secureTextFields["password-field"].tap()
        app.secureTextFields["password-field"].typeText("password123")

        app.buttons["Login"].tap()

        XCTAssert(app.staticTexts["Welcome"].waitForExistence(timeout: 5))
    }

    func testBiometricLogin() throws {
        app.buttons["Use Face ID"].tap()
        // Simulate biometric match in simulator
        let springboard = XCUIApplication(bundleIdentifier: "com.apple.springboard")
        springboard.buttons["Matching Face"].tap()
        XCTAssert(app.staticTexts["Welcome"].waitForExistence(timeout: 5))
    }
}

Espresso (Android Native)

Google's UI testing framework for Android. Synchronises with main thread automatically. No explicit waits needed.

// LoginTest.kt
@RunWith(AndroidJUnit4::class)
class LoginTest {

    @get:Rule
    val activityRule = ActivityScenarioRule(LoginActivity::class.java)

    @Test
    fun successfulLogin() {
        onView(withId(R.id.email)).perform(typeText("user@example.com"), closeSoftKeyboard())
        onView(withId(R.id.password)).perform(typeText("password123"), closeSoftKeyboard())
        onView(withId(R.id.login_button)).perform(click())

        onView(withId(R.id.home_screen)).check(matches(isDisplayed()))
    }

    @Test
    fun showsErrorForInvalidCredentials() {
        onView(withId(R.id.email)).perform(typeText("wrong@example.com"))
        onView(withId(R.id.password)).perform(typeText("wrongpassword"))
        onView(withId(R.id.login_button)).perform(click())

        onView(withText("Invalid credentials")).check(matches(isDisplayed()))
    }
}

BrowserStack / AWS Device Farm

Real device cloud testing. Run Appium scripts across 3,000+ real device/OS combinations without owning hardware.

# BrowserStack Appium
options = UiAutomator2Options()
options.platform_name = "Android"
options.set_capability("bstack:options", {
    "deviceName": "Samsung Galaxy S23",
    "osVersion": "13.0",
    "projectName": "MyApp",
    "buildName": "CI Build #123",
    "sessionName": "Login Flow",
    "userName": os.environ["BROWSERSTACK_USERNAME"],
    "accessKey": os.environ["BROWSERSTACK_ACCESS_KEY"],
    "networkLogs": True,
    "video": True,
})

driver = webdriver.Remote(
    "https://hub-cloud.browserstack.com/wd/hub",
    options=options,
)

# GitHub Actions with BrowserStack
- name: Run mobile tests on BrowserStack
  env:
    BROWSERSTACK_USERNAME: ${{ secrets.BROWSERSTACK_USERNAME }}
    BROWSERSTACK_ACCESS_KEY: ${{ secrets.BROWSERSTACK_ACCESS_KEY }}
  run: pytest tests/mobile/ --html=report.html

Mobile-Specific Test Scenarios

• Network conditions — test on 3G, 4G, offline (Charles Proxy, Network Link Conditioner)
• Interruptions — incoming call, notification, low battery while completing a transaction
• Permissions — deny camera/location permission mid-flow
• Orientation — rotate during a multi-step form
• Deep links — app opens from push notification or external URL
• App backgrounding — background mid-flow, foreground, verify state preserved
• OTA updates — what happens if app updates while user is on a screen

Common Failure Cases

Appium tests pass on emulator but fail on real devices due to element ID differences Why: resource IDs on emulators can differ from those on physical devices, especially across manufacturer skins (Samsung One UI, MIUI). Detect: tests green in CI against emulator-5554 but fail when run via BrowserStack on Samsung Galaxy devices. Fix: use accessibility IDs or content descriptions as locators instead of resource IDs; validate the locator strategy against at least two real-device OEMs before adding to the suite.

XCUITest simulator tests miss biometric and permission dialogs Why: the simulator handles Face ID and permission dialogs differently than physical devices; tests that tap through dialogs on simulator silently skip the system alert on device. Detect: testBiometricLogin passes on simulator but hangs or fails on a physical iPhone in BrowserStack. Fix: add explicit handling for system alerts (addUIInterruptionMonitor) and use XCUIApplication(bundleIdentifier: "com.apple.springboard") only for simulator; gate biometric tests to run on physical device farms only.

Network condition tests not representative — always run on fast Wi-Fi Why: CI and local emulators default to full-speed networking; mobile-specific failure modes (3G latency, offline mid-transaction) are never exercised. Detect: app receives production crash reports for SocketTimeoutException under LTE conditions not seen in testing. Fix: add at least one test run using Network Link Conditioner or BrowserStack's network profiles set to "3G - Good" and verify the app shows a graceful loading or retry state.

App state not reset between tests — bleed-over causes flaky order Why: no_reset: False is only set in some configurations; prior test data (login session, partially filled forms) leaks into the next test. Detect: tests pass individually but fail in batch runs; failure order changes between runs. Fix: set no_reset: False and full_reset: True in the Appium options fixture, or implement a clear_app_data() helper called in tearDown; confirm each test starts from a clean install state.

Orientation change during multi-step form loses state silently Why: Android activity restarts on rotation by default; if the fragment doesn't save and restore ViewModel state, form data is lost without an error message. Detect: rotate the device on step 2 of checkout; verify step 2 data is still populated after rotation. Fix: write a dedicated rotation test using driver.rotate(ScreenOrientation.LANDSCAPE) mid-form; fix the ViewModel to use SavedStateHandle if state is lost.

Connections

qa-hub · qa/cross-browser-testing · qa/test-environments · technical-qa/browser-automation-patterns · technical-qa/test-architecture

Open Questions

• What testing scenarios does this technique systematically miss?
• How does this approach need to change when delivery cadence moves to continuous deployment?