Android Emulator QA Expert

Automate Android testing and visual QA using the Emulator.

For Vibe Coders

Use ADB commands and Claude Vision to QA Android apps without writing test code.

ADB Basics

Device Connection

# List connected devices/emulators
adb devices

# Connect to specific emulator
adb -s emulator-5554 shell

Screenshot

# Capture screenshot
adb exec-out screencap -p > android-screen.png

# With device selection
adb -s emulator-5554 exec-out screencap -p > screen.png

Screen Recording

# Start recording (max 3 minutes)
adb shell screenrecord /sdcard/recording.mp4

# Stop with Ctrl+C, then pull file
adb pull /sdcard/recording.mp4 ./recording.mp4

Emulator Commands

Launch Emulator

# List available AVDs
emulator -list-avds

# Launch specific AVD
emulator -avd Pixel_7_API_34 &

Quick Boot

# Cold boot (fresh start)
emulator -avd Pixel_7_API_34 -no-snapshot-load

# Quick boot (resume state)
emulator -avd Pixel_7_API_34

Automated QA Flow

Multi-Device Testing

#!/bin/bash
# qa-android-devices.sh

devices=("Pixel_4_API_34" "Pixel_7_API_34" "Pixel_Tablet_API_34")

for device in "${devices[@]}"; do
  echo "Testing on $device..."

  # Launch emulator
  emulator -avd "$device" -no-window &
  sleep 30  # Wait for boot

  # Install app
  adb install -r app/build/outputs/apk/debug/app-debug.apk

  # Launch app
  adb shell am start -n com.example.app/.MainActivity

  sleep 3

  # Screenshot
  adb exec-out screencap -p > "qa-${device}.png"

  # Kill emulator
  adb emu kill
done

echo "Screenshots ready for review!"

Dark Theme Toggle

# Enable dark theme
adb shell "cmd uimode night yes"
sleep 2
adb exec-out screencap -p > dark-mode.png

# Enable light theme
adb shell "cmd uimode night no"
sleep 2
adb exec-out screencap -p > light-mode.png

Font Scale Testing

# Large font
adb shell settings put system font_scale 1.3
sleep 2
adb exec-out screencap -p > large-font.png

# Default
adb shell settings put system font_scale 1.0

Deep Linking

# Open specific activity via intent
adb shell am start -a android.intent.action.VIEW \
  -d "myapp://settings" com.example.app
sleep 2
adb exec-out screencap -p > settings.png

App Interaction

Tap/Click

# Tap at coordinates (x, y)
adb shell input tap 540 1200

Swipe

# Swipe down (scroll)
adb shell input swipe 540 1000 540 200 300

Text Input

adb shell input text "Hello%sWorld"  # %s = space

Common Checks for Claude Vision

Integration with Claude

Drag screenshots into Claude and ask:

"Is this following Material Design guidelines?"
"Check for Android-specific UI issues"
"Compare phone vs tablet layout"

Use when: Android visual testing, emulator automation, multi-device QA