It is no secret that Android is loved by millions of people around the world. Created and developed by Google, it would be most developers’ dream job. That being said, there are a lot of job opportunities that do require you to be proficient with Android development. These are typically high-end jobs that offer awesome salaries and great work benefits.
However, before you can start reaping the benefits of such a job, you need to get it first. To do so, you will have to pass a job interview which will involve Android interview questions. It’s best you study these Android interview questions and answers before your interview! And oh – what a coincidence! – you are a reading an “Android interview questions” tutorial right now!
In this tutorial, we shall talk about 20 of the most popular and commonly asked questions related to Android development. To show diversity, we’ll cover 10 basic questions, and then move on to some more advanced stuff for the leftover 10.
Table of Contents
- 1 Introduction
- 1.1 Question 1: What is Android?
- 1.2 Question 2: What is ‘application’?
- 1.3 Question 3: What is the place where the GUI of Android is stored called?
- 1.4 Question 4: Define ‘implicit’ and ‘explicit’ intents.
- 1.5 Question 5: Name the four Java sensor classes.
- 1.6 Question 6: Can you run Java on Android using the standard bytecode?
- 1.7 Question 7: Name a few pros of the Android system.
- 1.8 Question 8: What does ‘ContentProvider’ do?
- 1.9 Question 9: What is the bytecode that Android uses?
- 1.10 Question 10: What is the use of an Adapter?
- 2 Android Interview Questions – Advanced
- 2.1 Question 1: What are the two main methods of storing data in Android?
- 2.2 Question 2: How can you use ‘intent’?
- 2.3 Question 3: What is ‘activity’?
- 2.4 Question 4: What are the core components of the Android OS?
- 2.5 Question 5: What’s the use of ‘handlers’?
- 2.6 Question 6: What is the best database for Android applications?
- 2.7 Question 7: Can two different Android apps share the same Linux ID?
- 2.8 Question 8: What’s DDMS?
- 2.9 Question 9: What is ‘ANR’?
- 2.10 Question 10: What’s the difference between an ‘AsyncTask’ and a ‘Thread’?
- 3 Conclusions
Let’s try to not get ahead of ourselves and just take it from the top. And in this case, the top means “the basic questions”.
Even though these questions are labeled as “basic”, you shouldn’t just discard them as common knowledge. Even if you’re an experienced Android developer, you might still find some things that are simply too difficult to explain. Thus, you have to search for an easier answer. And these basic questions provide just that – a chance to learn how to deal with difficult stuff quickly! This is very important to your employers, so don’t just brush these “basic” Android interview questions and answers off – give them a try!
Question 1: What is Android?
Most of the Android job interviews that you’ll attend are bound to have this as their very first question. In answering, you not only demonstrate that you know what Android is (and you’re not just a random person off the street), but also show your ability to form your definitions.
Quite simply, Android is a mobile operating service. As I’ve mentioned in the beginning, it was created and developed by the team at Google. Its code is based on the open-source Linux kernel, and it (Android) was designed to primarily be used on touchscreen devices, thus eventually becoming the biggest rival to iOS.
Question 2: What is ‘application’?
The Application class can be considered as the baseline of Android – it is the key class that contains all of the other important elements for other actions and services that Android performs. Probably needless to say, but this class is initialized before anything else in Android once the program is launched.
Question 3: What is the place where the GUI of Android is stored called?
First of all, let’s establish what a ‘GUI’ is.
GUI means Graphical User Interface. It is a tool that helps the developers to simulate certain specific scenarios and see them in the way that a user of the app would see it.
Android’s GUI is stored within what is called an “Android SDK”. For an easy comparison of what that is, imagine that you were planning to go and work in the garden. What would you need to do that? That’s right – tools. Where are the tools usually stored? That’s right – the shed. The Android SDK is the equivalent of a shed – it stores all of the essential and necessary tools for the developer’s easy access.
It’s quite an extended answer, but remember – the more Android interview questions that you expand on, the more knowledgeable you will look in front of your potential employer.
Question 4: Define ‘implicit’ and ‘explicit’ intents.
In addition to definitions, you might also encounter a lot of comparison-based Android developer interview questions during your job interview. When it comes to the basic part, these would usually require you to compare some very fundamental Android variables. The same applies in this case.
When you imply an implicit intent, the Android interface checks the system for settings that might help you perform your task. The explicit intent, on the other hand, is when you specify the components that your system should use while performing the task. To oversimplify, you just order the system to do as you say and leave little room for agility.
Question 5: Name the four Java sensor classes.
Android uses four specific Java classes that are based on sensors. These are as follows: Sensor, SensorEvent, SensorEventListener, and SensorManager.
Question 6: Can you run Java on Android using the standard bytecode?
No, no you can’t. If this is one of the Android interview questions that your employers will ask a follow-up question (in this case it would most likely be “why?”), you can just say that Android is based on and uses a different, specific type of bytecode.
Question 7: Name a few pros of the Android system.
Sometimes, you might get this type of Android interview questions – the opinion-based ones. This is pretty cool because you are completely free to tell your opinion on the matter, but (at least in this case) can be sure that it’s completely subjective.
Why do employers even ask such questions, then? Well, that’s pretty easy – to see what you value and prioritize the most when it comes to Android. It’s a nice “trick question” for the employers to check if you’re going to go on a rant that you memorized on the internet, or if you’re thinking about it.
Since it’s quite subjective, there is no one true or false answer. However, just to give you a few examples of what a lot of other people proclaim to be the best features: Android being open-source, being supported by a wide variety of hardware developers, being based on Java and so on.
Question 8: What does ‘ContentProvider’ do?
This command is used to access specific types of organized and structured sets of data. You can view it as a sort of a medium – it connects strings of code with other, different strings of code.
Question 9: What is the bytecode that Android uses?
If you remember one of the previous Android interview questions and answers in this tutorial (namely, Question 6), you probably know that Android cannot use the Java bytecode because it has one of its own. This bytecode is called Dalvik Virtual Machine (DVS).
Question 10: What is the use of an Adapter?
In the Android system, adapters are used to connect the AdapterView (whatever that might be; it depends on the specific scenario in which it is used) with an external source of data.
Android Interview Questions – Advanced
Now we can transition to the advanced part of the tutorial. However, there is one more thing that you should know before continuing – and it has to do with the term “advanced”.
If you’ve never been to a job interview where you would have to answer Android interview questions, it might get pretty confusing. You might think that the term “advanced Android developer interview questions” means something grandiose – that you’ll have to write a five hundred page-long essay on why Android is the best or something. I’m here to tell you not to worry about it.
In the context of this tutorial, the phrase “advanced Android interview questions” simply means that your potential employers are going to want you to show a bit more of the in-depth knowledge that you have about Android. Whether it be to expand on certain answers or to answer some technical questions – relax!
Now that that’s out of the way, let’s get straight back into the Android questions.
Question 1: What are the two main methods of storing data in Android?
These methods are Shared Preferences and Internal Storage. Shared Preferences are mainly used to store key-value pairs, which can sometimes be a limitation. Internal Storage, on the other hand, stores all of the developer’s private data and information within the device’s inner memory.
Question 2: How can you use ‘intent’?
When it comes to advanced Android interview questions and answers, they are most likely to have more than one answer (at least in most cases). This question is no exception.
There are three common situations where you would use ‘intent’: to start the device, to start a specific activity and to start a broadcast.
Question 3: What is ‘activity’?
A clear example of trick Android interview questions. In truth, this is a very simple and straightforward question with an even simpler answer – activity is the container in the user interface. Why is this placed in the “advanced” category, then?
As I’ve mentioned earlier, you are bound to get some trick Android interview questions in your job interview. Your potential employer might want to throw you off balance with sneaking in an actual super-easy question. Furthermore, you would be surprised at how many people do have a hard time defining Android ‘activities’.
Question 4: What are the core components of the Android OS?
In total, there are five main components essential to Android – Activity, Content Provider, Fragment, Intents, and Services.
Question 5: What’s the use of ‘handlers’?
In Android, handlers are most commonly used to pass communication between different threads. This is especially true in the scenario where you would use a handler to pass an action from a background thread to the main one.
Question 6: What is the best database for Android applications?
This is considered to be one of the more advanced Android interview questions mostly because you either know it, or you don’t.
The best open-source database for Android apps is SQLite.
Yes, they can. However, needless to say, it doesn’t happen just like that.
For the two apps to hold a shared Linux ID, they would both have to have signed with the same certificate. In addition to that, they would then also share the same VP.
Question 8: What’s DDMS?
DDMS abbreviates to the Dalvik Debug Monitor Server. It is a bug monitoring server that comes together with the Android OS itself. It’s responsible for tracking errors, incoming calls, SMS, location data spoofing and – naturally – debugging.
Question 9: What is ‘ANR’?
Application Not Responding. It is a pop-up that the developer would receive if he or she had initiated too many processes at the same time. It’s Android’s way of telling you that you’ve crashed the system.
Question 10: What’s the difference between an ‘AsyncTask’ and a ‘Thread’?
AsyncTasks are used to work with short-running processes (up to 5 seconds), while threads handle longer ones.
In this tutorial, we’ve covered both the basic and the more advanced Android interview questions that you might receive during your Android development job interview.
Needless to say, we’ve only scratched the surface with these Android questions. There are hundreds (if not thousands!) more, but it would be almost impossible to fit them all into this tutorial. However, at least when it comes to the Android developer interview questions, the ones provided in this guide should have given you some sort of an idea of what to expect in your interview, at the very least.
Remember to get a good night’s sleep, eat a healthy breakfast and try not to stress about it too much. Being nervous is completely normal and understandable – freaking out isn’t all that great.
Don’t try to superficially impress your employers – just be yourself! That always turns out as the better choice to make. Instead, show them who you are as a person. Skills can be acquired, and a lot of potential employers are ready to teach them. Character traits, on the other hand, are a bit different – if you act like a jerk during the job interview, that is the last time you will most likely see that company.
I honestly hope that the questions and answers provided in this tutorial will help you score that dream job as an Android developer. Remember – study hard, leave some time for yourself, and, when the time comes to show your potential employers what you’ve got – kick some butt!