The 7 Best Android Developer Interview Questions in 2023
What are the top Android developer interview questions? Here you get the top Android interview questions to ask at your next interview.
Want to learn more? Read on!
Interviewing Android developers
Android developers are mobile developers who are specialized in developing Android applications, using mainly Kotlin and Java as programming languages. One or both of the languages can be used to develop apps.
But how do you interview Android developers and identify those with the strongest skills? Here are our top questions to ask during an interview:
Beginner Android developer interview questions
What are the top junior Android developer interview questions? Here’s what you need to know!
1. Describe the Android architecture.
Answer:
The Android architecture refers to the operating systems, applications and middleware of the Android stack. Each layer supports the layer above it. The five layers that make up the Android architecture are:
Linux Kernel: The Linux Kernel is responsible for device management, drivers, memory management, power management, and resource access.
Libraries: One of the layers is a set of libraries with the open-source web browser WebKit, library libc, libraries to play and record audio and video, SSL libraries, and SQLite database for sharing data and storage.
Android Runtime: Core libraries together with DVM (Dalvik Virtual Machine) or ART (Android Runtime) are helpful for running an Android application. DVM is optimized for mobile devices and it offers fast performance and better memory management. ART replaces DVM for executing Android apps from the Android Lollipop 5.0 version.
Android Framework: This layer consists of Android APIs such as data, resources, User Interface, package managers, and more. It provides interfaces and classes for the development of Android applications.
Android Applications: This layer consists of applications like contacts, settings, games, browser, and so on that make use of the Android Framework, which in turn uses runtime and libraries.
2. What disadvantages does Android have?
Answer:
There aren’t any clear guidelines on how to adapt all Android applications for different OS versions and upgrades because Android is open-source and the system has been released on different devices. So if one app runs on one version, it might not run on a different version.
Plus, as mobile devices are shaped and sized differently, developers need to create apps that can adjust correctly to the right device.
3. What does the build process look like in Android?
Answer:
The build process in Android features three steps. These are:
1) The first step is the compilation of the resources folder that uses the Android Asset Packaging Tool (AAPT), which is compiled into a single class file (R.java) with only constants.
2) The second step is a Java source code that needs to be compiled to .class files with javac. These are then converted to Dalvik bytecode with the “dx” tool with the final output file classes.ex.
3) In the third step, the Android apk builder is required to take all the inputs and build the Android Packaging Key (APK) file.
4. List tools that are available to Android developers and explain their functions.
Answer:
Various tools help Android developers, including these ones:
Android Emulator: The Android Emulator is designed to run processes within a virtual device and it’s the implementation of the Android Virtual Machine. This tool is used to test and debug Android applications.
Android Debug Bridge: ADB is a command-line debugging application that’s doled out with the Android Software Development Kit. This tool is used to communicate with the device and supports with installing and debugging applications.
Android Software Development Kit. The tool is used to generate and handle Android Virtual Devices and SDKs. You can specify the supported SDK version, screen resolution, storage in the SD card, and more.
Android Asset Packaging Tool. The AAPT builds the .apk distributable Android package file.
Advanced Android developer interview questions
Want to know what the best senior Android developer interview questions are? Here’s what you need to know!
5. Define DDMS.
Answer:
DDMS, the Dalvik Debug Monitor Service, ships with Android. It includes various debugging features such as:
Location data spoofing
Screen capture
Port-forwarding services
Simulating network state, speed, and latency
Incoming call and SMS spoofing
6. What are the different launch modes in Android?
Answer:
The different launch modes in Android are:
Standard: This launch mode generates a new instance of the activity in the task from which it originates. Multiple instances can be created of the same activity and they can be added to the same or different tasks.
SingleTop: The SingleTop launch mode is similar to the Standard launch mode. However, a new instance won’t be created if there is a previous instance of the activity on the top of the stack. Instead, the intent will be sent to the existing instance of the activity.
SingleTask: The SingleTask launch mode always creates a new task and pushes a new instance to the task as the root.
SingleInstance: This is the same as the SingleTask launch mode. However, the the difference is that the system doesn’t launch new activities in the same task but is instead launched in a separate task.
7. Explain the difference between Serializable and Parcable. Which one is better for Android?
Answer:
Serializable is a standard Java interface. You mark a class Serializable by implementing the interface. In that case, Java will automatically serialize it in some situations.
Parcelable is an Android interface that you use to implement the serialization. It was created to be more efficient than Serializable and to fix some problems with the Java serialization scheme.
Over to you!
That’s it! Now you know what the top Android developer interview questions are.
However, interviews are just one part of the process. You also need to assess your candidates’ skills. And that’s done with assessment tests and live coding interviews.
CodeSubmit is an industry-leading software that helps you assess your candidates and supports languages like Kotlin and Java.
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