Performance Optimization

1. What are the different types of performance issues you have encountered in Android apps? How did you identify and resolve them?

Answer: The candidate should be able to describe different types of performance issues such as slow UI rendering, slow network requests, memory leaks, and excessive CPU usage. They should also be able to explain how they identified these issues using tools like Android Profiler, and how they resolved them using techniques such as caching, improving network requests, optimizing memory usage, and using asynchronous operations.

Example: In one of my previous projects, we noticed that our app’s UI was taking a long time to load. We used Android Profiler to identify the cause and found that we were doing too much work on the main thread, which was causing the UI to freeze. To resolve this issue, we moved the heavy processing to a background thread using AsyncTask and also implemented caching for frequently used data to reduce the number of network requests.

Введение в разработку приложений для ОС Android

Березовская Ю.В., Юфрякова О.А., Вологдина В.Г., Озерова О.В., Куликов Э.Е., Латухина Е.А., Пархимович М.Н.

Учебное пособие. — 4-е изд.

Учебное пособие ориентировано на людей, имеющих небольшой опыт программирования на современных языках и желающих научиться основам программирования для операционной системы Android. В издании рассматриваются следующие вопросы: предварительная подготовка компьютера для разработки под Android (установка и настройка программного обеспечения); проектирование и разработка приложений разного уровня сложности; использование возможностей смартфона (сенсорный экран, камера, звук, GPS); подключение и использование готовых библиотек; разработка простых игровых приложений; основы разработки мобильных HTML5-приложений с использованием Intel XDK.

🔐 Protect your privacy with UserVPN

Want to use the internet спокойно without tracking and restrictions?
UserVPN encrypts your traffic, hides your IP, and makes your online activity much harder to track.

📱 Fast connection
🌍 Access to the resources you need
🛡 One-tap data protection

Official page

If the app doesn’t suit you — there’s an alternative 👇
We publish fresh VPN configs every day:

📢 Channel: @uservpn
🤖 Bot: @openvpn24_bot

Testing

1. What is unit testing in Android? How does it help in improving the quality of Android apps?

Answer: Unit testing is the process of testing individual units or components of an Android app in isolation to verify that they work as expected. It helps in identifying bugs or errors in the code and ensures that the app functions correctly. Unit testing also helps in making the code more modular and maintainable. For example, using JUnit and Mockito, a developer can write tests for the business logic of an app to ensure that it meets the desired requirements.


2. What is UI testing in Android? How does it differ from unit testing?

Answer: UI testing is the process of testing the user interface of an Android app to ensure that it works as intended. Unlike unit testing, UI testing involves testing the app as a whole, including the interaction between different components. UI testing is generally used to ensure that the app’s UI is intuitive and easy to use, and that it functions correctly across different devices and screen sizes. Espresso is a commonly used framework for UI testing in Android.

3. What is integration testing in Android? How does it differ from unit testing?

Answer: Integration testing is the process of testing the integration between different components or modules of an Android app. It involves testing the interaction between different units or components, such as the interaction between the UI and the data layer. Integration testing ensures that the app functions correctly as a whole and that all the components work together seamlessly. Unlike unit testing, integration testing involves testing multiple components together.

4. What is a test double in Android testing? Give an example.

Answer: A test double is a type of testing tool used to replace a component or module in an Android app with a substitute that mimics the behavior of the original component. This is done to isolate the component being tested from other parts of the app, such as dependencies or external APIs. Examples of test doubles include mock objects, stubs, and fakes. For example, a mock object can be used to simulate the behavior of an external API, allowing developers to test the behavior of the app without relying on the actual API.


#Testing

SDL2 for PlayStation 2 and PC Homebrew Lessons

Lesson: Project Setup

https://youtu.be/HvEFyiR-9TQ

Whitaker Rob. Developing Inclusive Mobile Apps: Building Accessible Apps for iOS and Android

2nd Edition. — Apress Media LLC, 2026. — 300 p. — ISBN-13: 979-8-8688-2808-9
By failing to consider those with needs different from our own, we are telling these people they are not welcome in our app, and therefore that technology as a whole is not for them. This is not hyperbole—23% of people in the US with a registered disability aren't online at all, that's three times more likely than the general population. When asked why they're not online, disabled respondents say their disability prevents them or that using the internet is too hard.
To help your apps combat the issue of digital exclusion, this book covers considerations and tools mobile developers, or anyone creating mobile experiences, can use to make mobile work better for those with disabilities—mental or physical—and how to create a better experience for everyone.
Software is not made up of cold, unthinking algorithms. Software is a craft in the truest s