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Mastering Android Screenshot Testing
Release with confidence: eliminate visual regressions across devices and configurations.
50% written · Updated
PDF & EPUB · DRM-free · Free updates · 60-day money-back guarantee
Why screenshot testing?
UI tests miss visual bugs
UI tests verify behavior but can't catch visual issues like misaligned layouts, unreadable text colors, or components in the wrong place.
Manual testing doesn't scale
Checking every combination of devices, themes, font sizes, and locales by hand becomes impossible as your app grows.
Refactor with confidence
Catch unintended visual changes when you update libraries or restructure code, so every UI change remains intentional.
What you'll learn
Screenshot testing fundamentals
Understand the core principles and when to use screenshot tests in your Android projects.
Tools and framework selection
Choose a screenshot testing framework and set standards that scale across your team.
Component and screen testing
Write robust tests for Compose components and screens, including dynamic content and animations.
Testing across configurations
Automatically test across themes, orientations, font sizes, locales, and device form factors.
CI/CD integration
Run screenshot tests in your pipeline and catch visual regressions before release.
Best practices
Learn the do's and don'ts that keep a test suite robust and free of flaky tests.
About the book
Testing an Android app means more than checking that it works. Its design needs to hold up on phones, foldables, and tablets, in light and dark mode, at different font sizes and in different languages, with a clean layout and legible text everywhere.
This book introduces screenshot testing (also called visual or snapshot testing): an automated approach that records a reference image of the expected design, then compares each test run against it to detect visual changes. It’s a natural complement to functional UI tests, which verify behavior but not appearance.
Rather than focusing on specific tools that quickly become outdated, the book teaches the principles that apply to every framework. It works through the questions developers actually face: when to use screenshot tests and when not to, what to verify, which frameworks and tools fit your workflow, how to generate tests from preview functions in Jetpack Compose, how to run tests in a CI/CD pipeline, and how to optimize the whole process. By the end, you’ll be able to pick the framework that suits your project and build a safety net that catches visual bugs before release.
Every concept is demonstrated with a demo mood tracker app, and all of the code is available online.
What's inside
Part 1
Introduction to Screenshot Testing
Mobile Testing Fundamentals
Challenges in Mobile Testing · Types of Mobile Testing
Introduction to Screenshot Testing
Understanding Screenshot Testing · Use Cases · When Not to Use Screenshot Testing · Impact on the Development Process
Part 2
Preparation for Screenshot Testing Automation
Establishing Standards and Guidelines for Screenshot Testing
Selecting Frameworks and Tools for Screenshot Testing
Screenshot Testing Frameworks · Screenshot Testing Tools and Services · Making the Right Choice for Your Project
Choosing Between Emulators and Physical Devices for Testing
When to Choose Emulators · When to Choose Physical Devices
Defining the Scope of Screenshot Testing
Setting Realistic Expectations · What to Verify with Screenshot Tests
Part 3
Implementing Screenshot Testing
Writing and Executing First Screenshot Tests
Prioritizing Test Scenarios · Designing Test Cases · Creating First Screenshot Tests
Handling Asynchronous Images
Providing Fake Images Using the coil-test Library · Using Inspection Mode to Display Fake Images · Choosing the Right Strategy for Your Framework
Generating Screenshot Tests for Preview Functions
Generating Screenshot Tests from Previews Using ComposablePreviewScanner and Roborazzi
Testing Screens in the Application
Testing Different States of the Screen · Interaction with the UI Before Capturing a Screenshot · Handling Delays
Appendices
Reference Guide for Local and Instrumentation Tests
Reference Guide for Non-functional Testing Types
Coming next
Added chapter by chapter, free for every reader.
- Testing components and screens against configurations
- Parameterized testing
- Screenshot storage strategies
- CI/CD integration
- AI tools
- Compose Multiplatform
About the author
Questions
Do I need experience with screenshot testing?
No. The book starts with the fundamentals and builds up to advanced techniques.
Which frameworks does it cover?
It compares six open-source frameworks, Android Testify, Compose Preview Screenshot Testing, Dropshots, Paparazzi, Roborazzi, and Shot, with hands-on examples in each, and helps you choose between them. It also shows how to generate tests from Compose previews with ComposablePreviewScanner and Roborazzi.
Is there a print version?
Not yet. The book is available as PDF and EPUB while it's being written, and a print edition is planned once it's finished.
Get the book
Pay what you want, from $14.99 (suggested $19.99). You get everything published so far, and every new chapter as it's released.
PDF & EPUB · DRM-free · Free updates · 60-day money-back guarantee
