Android Interview Questions and Answers

Introduction

The popularity of Android is growing exponentially almost every day. This is the reason why people love to choose android developer as their primary career choice. In this article, we will discuss on popular questions and answers that are usually asked by android developers.

The discussion starts with basic concepts, then it goes tricky later to check the actual proficiency of android professionals. Let us have a quick look at popular Android developer interview questions and answers step by step.

Android Interview Questions And Answers

• Why choose Android as your primary career choice?
• What is the significance of SDK in Android development?
• Name the popular key components of Android architecture?
• What is the role of an Android framework in android architecture?
• Name the technology or tool with the ability to work with Zip files?
• What do you understand by having an emulator in Android environment?
• How to create a new Android project within android IDE?
• What do you understand by Intents in Android IDE?
• How will you differentiate Activities and Services in Android environment?
• Name the essential items that need to be created first before you initialize some android project?
• How should android developer set up the Android-powered device before starting any actual development?
• As an android developer, how will you enumerate the steps necessary to created bounded services through AIDL?
• How will you define AIDL in Android environment?
• What is the best time for killing any foreground activity?
• How to add any fragment without using user interface?
• Is it possible to delete icons and widgets from home screen of Android device?
• How will you differentiate nine-patch image from regular bitmap image?
• Name the programming language you have to work on during application development?
• Why developers prefer XML-based layouts over other?
• How will you set Orientation in Android IDE?
• Which tools are used with android IDE to detect app logs?
• Name few mobile automation testing tools you have heard about?
• Should testing be performed on real devices or emulators?
• How can you optimize CPU usage and memory utilization?
• What do you understand by android testing strategy?
• Can you explain about best practices for Android testing?
• What are the common types of bugs detected during android app testing?
• Do you know anything about Robo-electric testing framework?
• What are the major criteria you need to focus on when performing end to end android app testing?
• When should you perform automation testing over manual testing?

Android Interview Questions and Answers

Android is a popular open-source operating system compatible with cell phones, tablets, or smartphones. Here we will discuss on popular interview questions that are divided into three sections.

These sections are – Android interview questions and answers, Android developer interview questions and answers and the last section is Android tester interview questions and answers. Let us discuss each of the sections in detail further.

Android Interview Questions and Answers

Question: 1. Why choose Android as your primary career choice?

Answer: Android is a Linux-based open-source OS equipped with highly functional components that help developers in writing rich android apps in the easiest way. This is the reason why Android has become a primary career choice for most of Java developers today.

Question: 2. What is the significance of SDK in Android development?

Answer: Android SDK (Software Development Kit) is a tool-kit that makes development task easy for the developer. The SDK enables the graphic interface for easy testing or debugging of code.

Question: 3. Name the popular key components of Android architecture?

Answer:

Question: 4. What is the role of an Android framework in Android architecture?

Answer: Here, you will find the complete collection of classes and methods that are necessary to write application code in the Android environment.

Question: 5. Name the technology or tool with the ability to work with Zip files?

Answer: The tool that can be used to work with ZIP components is AAPT (Android Asset Packaging Tool) that handles creation, extraction and viewing all the ZIP contents.

Question: 6. What do you understand by having an emulator in Android environment?

Answer: An emulator allows you to play around the interface and it feels like you are working on actual mobile devices only. With the help of an emulator, you can write codes or debug codes securely especially during initial design phases.

Question: 7. How to create a new Android project within android IDE?

Answer: You have to use an “activityCreator” to start a new android project within android IDE. An “activityCreator” is made up of the shell script that will help you in creating fresh file structure to write codes.

Question: 8. What do you understand by Intents in Android IDE?

Answer: Intents are used to display notification messages on android enable devices. These notifications may be alert messages or any other notifications. The best part is that Android users can also respond to these intents whenever required.

Question: 9. How will you differentiate Activities and Services in Android environment?

Answer: Activities don’t run continuously and they can be closed or terminated anytime based on user choice. On the other hand, Services run continuously and independently behind the scenes regardless of whether activities are executed together or not.

Question: 10. Name the essential items that need to be created first before you initialize some android project?

Answer: The essential items that should be present every time android project is created includes –

Android Developer Interview questions and answers

Question: 11. How should Android developer set up the Android-powered device before starting any actual development?

Answer:

• Keep your Android application in debug mode through an Android manifest framework.
• Turn on “USB Debugging” option on your device.
• Set up system nicely so that it can detect device quickly.

Question: 12. As an Android developer, how will you enumerate the steps necessary to created bounded services through AIDL?

Answer:

• Create AIDL file to define the programming interface.
• Implement the interface and
• Expose the interface

Question: 13. How will you define AIDL in the Android environment?

Answer: Android Interface Definition Language (AIDL) maintains the communication gap between client and service through IPC. With AIDL, you can break down the objects into small primitives that can be understood by the Android IDE. These primitives can be quickly understood by android without consuming too much memory.

Question: 14. What is the best time for killing any foreground activity?

Answer: Foreground activity is taken as very important part of the script and it is killed only when consuming too much memory. Once it is killed interface again becomes responsive to the user.

Question: 15. How to add any fragment without using user interface?

Answer: Yes, it is possible to add fragment without any assistance of user interface. For this purpose, you should use the method add(Fragment, string) to add a fragment from the particular activity.

Question: 16. Is it possible to delete icons and widgets from home screen of Android device?

Answer: Yes, it is possible to delete icons and widgets from home screen of Android device by long pressing and holding that particular icon. Now drag the selected item downward screen and delete it finally.

Question: 17. How will you differentiate nine-patch image from regular bitmap image?

Answer: Nine-patch image works on nine parameters when resizing an image that includes four corners, 4 edges, and one axis. At the same time, Regular bitmap images work on the overall background image.

Question: 18. Name the programming language you have to work on during application development?

Answer: The most popular programming language used for app development is Java that is taken as an ideal choice for Android developers to create or deploy rich android apps in android environment.

Question: 19. Why developers prefer XML-based layouts over other?

Answer: The XML-based layout is a primary choice for Android developers because it provides the most consistent look to the Graphical Interface. This layout allows you to store layout details in XML files while other important information can be stored with source files.

Question: 20. How will you set Orientation in Android IDE?

Answer: To manage orientation in android development, you should use the command setOrientation() for VERTICAL or HORIZONTAL alignments.

Android Testing Interview question and answers

Question: 21. Which tools are used with android IDE to detect app logs?

Answer: Access the “Tools” option from Android SDK and click on ‘Monitor.bat’ file to check the app logs. You can also check various free tools on Google Play to capture the app logs.

Question: 22. Name few mobile automation testing tools you have heard about?

Answer:

• High paid tools - Ranorex, Silk Mobile, SeeTest, etc.
• Free testing tools – KIF, Robotium, Calabash, and Appium etc.

Question: 23. Should testing be performed on real devices or emulators?

Answer: As per my opinion, there are lots of things that you cannot check on emulators but same can be easily performed on real devices like battery status, phone calls, messaging, memory card checks etc. This is the reason why you should go on testing with real devices instead of emulators.

Question: 24. How can you optimize CPU usage and memory utilization?

Answer: On Google Play, there are multiple tools that help you with effective memory utilization and improved CPU usage. You can also use Systrace feature within Android IDE for the same purpose.

Question: 25. What do you understand by android testing strategy?

Answer: The effective android testing strategy should pass through following tests – Unit testing, Integration testing, Operational testing, system testing etc.

Question: 26. Can you explain about best practices for Android Testing?

Answer:

• The developer should create test cases during code writing.
• Test cases should also be stored along with source code
• Every time you make changes to source code, perform continuous integration regressively.
• You should use real devices instead of emulators.

Question: 27. What are the common types of bugs detected during android app testing?

Answer:

• Critical – Real device may crash when a particular function is performed on it.
• Major – Unable to perform particular feature you want to perform instantly.
• Block – Device will stop working until you don’t reboot it.
• Minor – These bugs are usually related to Graphical interface only.

Question: 28. Do you know anything about Robo-electric testing framework?

Answer: This is an advanced testing mechanism that directly executes test cases on JVM without any need of real devices or emulators.

Question: 29. What are the major criteria you need to focus on when performing end to end android app testing?

Answer:

• App Installation
• App launch without network
• App un-installation
• App Orientation

Question: 30. When should you perform automation testing over manual testing?

Answer: Manual testing should be used for simpler test cases when an application needs to be tested once or twice only. At the same time, Automation testing can be performed for complex scenarios too where regression testing is the primary requirement.