Android Developer Interview Questions and Answers

Android Developer Interview Questions and Answers

Introduction to Android:

Operating Systems have developed a lot in last 16 years. Starting from black and white phones to recent smart phones or mini computers, mobile OS has come far away. Especially for smart phones, Mobile OS has greatly evolved from Palm OS in 1996 to Windows pocket PC in 2000 then to Blackberry OS and Android.

 One of the most widely used mobile OS these days is ANDROID. Android is a software bunch comprising not only operating system but also middleware and key applications. Android Inc was founded in Palo Alto of California, U.S. by Andy Rubin, Rich miner, Nick sears and Chris White in 2003. Later Android Inc. was acquired by Google in 2005. After original release there have been number of updates in the original version of Android.

Android is a mobile operating system developed by Google, based on the Linux kernel and designed primarily for touchscreen mobile devices such as smartphones and tablets. This project is led by Google. Android is an open source software stack created for a wide array of devices with different form factors. The primary purposes of Android are to create an open software platform available for carriers, OEMs, and developers to make their innovative ideas a reality and to introduce a successful, real-world product that improves the mobile experience for users.

Android applications are written in java programming language. Android is available as open source for developers to develop applications which can be further used for selling in android market. There are around 200000 applications developed for android with over 3 billion+ downloads. Android relies on Linux version 2.6 for core system services such as security, memory management, process management, network stack, and driver model. For software development, Android provides Android SDK (Software development kit).

The first version 1.0 of android development kit (SDK) was released in 2008 and latest updated version is  Android 10.  

Code nameVersionAPI level
Android 10






API level 29

API level 28

API level 26, 27

Nouga7.0.0-7.1.0API level 24, 25
Marshmallow6API level 23
Lollipop5.0-5.1API level 21, 22
KitKat4.4 – 4.4.4API level 19, 20
Jelly Bean4.1.x-4.3.xAPI level 16, 17, 18
Ice Cream Sandwich4.0.3 – 4.0.4API level 15, NDK 8
4.0.1 – 4.0.2API level 14, NDK 7
Honeycomb3.2.xAPI level 13
3.1API level 12, NDK 6
3API level 11
Gingerbread2.3.3 – 2.3.7API level 10
2.3 – 2.3.2API level 9, NDK 5
Froyo2.2.xAPI level 8, NDK 4
Eclair2.1API level 7, NDK 3
2.0.1API level 6
2API level 5
Donut1.6API level 4, NDK 2
Cupcake1.5API level 3, NDK 1
 Petit Four1.1API level 2
(No code name)1API level 1

What is Android?

What is Android Architecture?

What is API Level?

What is NDK?

Explain Android application Architecture?

What are the advantages of android?

What are the Uses of API Level in Android?

What is an APK File?

What is the JobScheduler API?

Why would I want to install an APK File?

What do you understand by having an emulator in Android environment?

What is an Android Manifest file?

How does the AOSP relate to the Android Compatibility Program?

Why cannot you run standard Java bytecode on Android?

How to create a new Android project within android IDE?

What is the Google Android SDK?

What are the seven lifecycle methods of Android activity?

What are intents?

What dialog boxes are supported in android?

What are typical subdirectories that the “res” directory does contain?

What is an Adapter in android?

What is ANR?

What is DDMS and what can it do?

What is AIDL?

What is GSON?

What is ADB?

What’s the difference between a Frame Layout and a Table Layout?

What is the difference between DP, SP and PX?

What are the methods to avoid memory leaks in Android?

How can we use escape characters as attributes?

What is the importance of settings permissions in app development?

What is a ContentProvider?

What is the role of compatibility that is used in Android?

What are “launch modes”?

What are the different types of services?

What is the difference between AsyncTask and Thread class?

What is the difference between Serializable and Parcelable?

What is a Hybrid mobile App?

What is Firebase?

What are the new features in Android 9(pie)?