I was called for a technical round. All the things went smoothly. I wasn't selected, but I was happy with the interviewer, the process, and everything. The interview was tough, though.

Explain MVP implementation for Login functionality. Show the flow diagram.

What is Dagger 2? Why do we use Dependency Injection? How do we use Dagger with the above example?

What is the difference between REST and SOAP?

How would you secure your application?

What is SSL pinning? Where should we store the certificate or PKI? If we are storing it in the app, then where should we store it in the app?

How does the Agile method work? What is a Retrospective?

What are design patterns?

Can we clone a Singleton object? What if we don’t want it to be cloned?

What is the Factory design pattern? What is the Builder pattern? Give me some examples for the Factory pattern.

What are Loopers? Why do we need them? Do Loopers work on the Main thread or a worker thread?

What are services? What are the different types of services? How does a bind service work?

What are the main pillars of OOPS?

What is Abstraction? What is the concept of Abstraction? Can we create an object of it? What is the difference between an Interface and an Abstract class?

What are custom components?

What are the benefits of using Kotlin?

What is the difference between Object-Oriented Programming and Procedural-Oriented Programming?

What is association?

What is Dependency?

What is the difference between dependency and association?

How do we prevent a parent class’s methods from being overridden in a child class?

Internal working of HashMap? Put and get methods.

What is the difference between HashMap and Hashtable?

What happens when a HashMap is modified during iteration? How do we avoid it?

What are extension functions?

What is null safety? What if we want to ignore null safety? (Ans: !!)

What is the difference between StringBuffer and StringBuilder?

Difference between == and equals()?

What are delegations in Kotlin?

How do we implement unit testing for the Login use case mentioned before? What kind of annotations are required?

What is a sealed class?

What is the difference between MVC and MVP?

What is the disadvantage of using Singleton?

What is DVM? How does it work?

What are the different constraints of the Constraint Layout? Why was it introduced? What are the advantages of it compared to RelativeLayout?

What are the reasons for app rejection on the Play Store?

Do we have switch-case in Kotlin? What can we use instead?