All Android Interview Questions at One Place

My Personal Experience with Many Companies A set of questions that I have accumulated over these 6.5 Years in preparation for my many Android Interviews Prep. I hope this will help everyone out here both for those who are looking for Job and also for those who want to Brush up their skills :) Hence sharing with you all

I will tell the most important and commonly asked questions First so that you can prepare accordingly

interview

— — — — — — — — — Activity/Fragment Part — — — — — — —

• Explain Activity Life Cycle and Most Importantly What will be the Life cycle (In Order) If Activity B is Launched from Activity A.
• Explain Fragment Life Cycle, How the Activity Life cycle and Fragment Life Cycle gets called In Order, RetainInstanceState in Fragment
• Fragment Add vs Fragment Replace, Explain with using Backstack and Without using backstack
• Activity Life cycle when Dialog is opened — (hint:- Don’t get confused b/w system-generated Dialog and your own app dialog)
• Why to use setContentView() in onCreate() callback method?
• LaunchModes in Android. What is onNewIntent (Very very important to understand it)
• Why it is recommended to use Default Constructor to create a Fragment

— — — — — — — Let’s move on to Service Part — — — — — — —

• On Which Thread Services Work? What are the Changes and Limitations introduced in the latest version of android regarding Services
• Services vs Intent Services — (Other than the Thread on which these both works 😜)
• Foreground Services and Background Services, Work Manager Role
• How Work Manager, Job Intent Service, Alarm Manager, Firebase Dispatcher are correlated, Which to use when

— — — — — — — — Broadcast Receiver — — - — — — —

• What’s Static and Dynamic Broadcast Receiver, What’re the changes Introduced in Latest version of Android regarding broadcast Receiver (hint:- Study Local Broadcast Manager)

— — — — — — — — — Content Provider — — — — —

• Explain Content Provider, What is Scheme? How can an Application Access database of another Application

— — — —— — — MVVM Design Pattern — — — — — —

• Design Pattern vs Architecture? Explain MVVM Design Pattern
• MVVM vs MVP Design Pattern (Nowadays MVI Design Pattern too)
• How ViewModel save Instance of UI? What’s the Role of Live Data in it, How Live data is different from Observer-Observable Pattern
• How will you write your own ViewModel if Android ViewModel is not there
• SharedViewModel, How to use it in Master-Detail kind scenarios for Fragment communication i.e Bye Bye Interface for Communication
• How UI state is managed with ViewModel, savedInstanceState, and Database?
• How to pass data in ViewModel constructor (hint:- ViewModel Factory)
• LiveData vs Mutable Live Data vs Mediator Live Data
• Map vs Switch Map in LiveData

— — — — — RxJava in Android (Event-Based) — — — — — -—

• Explain RxJava? What are Observables and Observers?
• Operators in RxJava. Map vs FlatMap in RxJava
• Subject in RxJava? Implement Own EventBus by RxJava
• How to implement Searching by RxJava
• Hang On ! Hope you have got huge knowledge Now. Let’s learn something which is equally important as the topics we studied above. It will worth your time

— — — — — Threading in Android (Do Study this one too )— — —

• Runnable vs Thread, the Basic difference between these two
• If Java already have threads/multi-threading Architecture than why Android needs to implement Handler
• What is Yarn, Join function. Sleep() vs Wait() in Threading (Usually asked in all companies)
• How can you implement Synchronization? Object Level lock vs Class Level Lock
• Thread Pool Executor (Must study if not heard of this). Explain ArrayBlockingQueue?
• Synchronize Keyword vs Synchronized Block (Very basic difference)

— — -— Mixup and Most Important Interview Questions — —

• ViewBinding vs DataBinding in Android, What is Binding Adapter? What’s the use of data tag in XML
• What is Dagger in Android? Implement own Manual Dependency Injection without Dagger, What is Module and Submodule in Dagger
• Build Type in Gradle? Explain Flavors in Gradle
• Handler, Looper, Handler vs HandlerThread
• Intent, Sticky Intent, Pending Intent. Purpose of Category in Intent

Thanks for Reading everyone!

I have written an article on the same, feel free to go through

This the experience I thought to share with you all, This list is by no means exhaustive. I will appreciate your thoughts on these questions in responses please feel free to raise PR if you were asked any question during your interview