Pick up the best and save it for future reference.

We struggle a lot learning small, basic and specific concepts. Here is my list of resources which may help you understand Android in a better way. A repository containing link/resources to small, basic as well as specific Android concepts.

Java

• Is Java pass by reference or value?

  Link 1

  Link 2

• Desugaring in Java

• Understanding Overloading and Overriding in Java

• Practive Overloading and Overriding Java

• When to use Static class and when Singleton?

  Link 1

  Link 2

• OnClickListener Internals

  Link 1

  Link 2

• Hashmap Internals

• ArrayList Internals

• LinkedList Internals

  Link 2

• Reflection in Java

  Link 1

  Link 2

• Garbage Collection

• Why Java is platform independent?

  Link 1

  Link 2

• Implements Runnable vs extends Thread

  Link 1

  Link 2

• Sparse Array vs Hashmap

• Static vs Singleton

• Lambda vs Anonymous Classes

• Stack vs Heap Memory

Android

• D8 vs R8

• ART vs Dalvik

• Android 11 Features

• FAQ on Scoped Storage

• Launch Modes

• Recent changes in Play store

• Activity Life Cycle

• Fragment LifeCycle

• Fragment Transition

• MVP vs MVVM vs MVI

  Link 1

  Link 2

• How MVI works

• How MVI works?

• Mediator vs Mutable Live Data

• Why and when to use Mediator Live Data

• Livedata transformations and Mdeiatot LiveData

• LiveData vs Observable Field

• Sealed Classes

• Data Classes

• setValue vs PostValue

• Exceptions vs Error

• Memory Leaks

• Solve OOM

• How to find OOM through hProf

• Understanding MultiDex

• Hardware Acceleration

  Link 2

• Understanding Webview methods

• Memory Leak in WebView

• WebView Best Practices

• WebView vs ChromeTab

• Custom Tab - What, How, When , Why

• Under FCM concepts for Foreground and Background

• Memory Management

  Link 2

  Link 3

• Understanding Job Scheduler

• If u need all time location access, what should you do?

• LayoutAnimation attribute for recycelrView not working for some devices?

• RecyclerView Internals

  Link 2

  Link 3

• Migration to Paging 3

  Link 2

• WorkManager vs JobScheduler

• Why & How DiffUtil?

• Lifecycle View in Android

  Link 2

• Kotlin Flow

• The SOLID Principles for Android Developers

• Kotlin Quick tips

• Jetpack Navigation between top-level destinations using Dagger-Hilt

• OkHttp vs Retrofit

• Understanding Android New Results API

• RecyclerView Tips

• LiveData with Coroutines and Flow

• Why @JvmOverloads in Kotlin

• Understanding Elvis Operator pitfalls

• Understanding Scoped Storage

• Understanding Android AllowBackup

• Understanding JSON Web Token

• ConstraintLayout

• Should we use largeHeap attribute in Android manifest

• Coroutines vs RxJava

• Mockito vs Mockk

• Best practices to test Static Methods

• Writing Testable Code

• JUnit Annotations

• Why Mockito can’t mock static methods

• apply vs let vs run in Kotlin

• Improve recyclerView Performance

• Understand Clean Architecture

• Memory management and Leaks

• Which context to use

• Steps to Build a quality app

• DDMS vs Android Profiler

• Activity Process LifeCycle

• System vs Data Notification - FCM

• Scheduler vs Dispatcher

• ViewModelFactory

• Custom Chrome Tabs

• Progressive vs Native App

• SDK vs Non SDK interfaces

• View Life Cycle

• How Vector drawable works

• Dagger vs Koin

• Handler vs HandlerThread vs Looper

• Enum vs Sealed Classes

• Understand Vector drawable path commands

• Custom Views performance

• Know About Memory Leaks

• FindViewById vs Synthetic Binding

• How Enums Impact performance

• Parcelable Interface implementation

Will be adding more here after sorting them out. You can follow this Github repository. Please contribute if you have more so that I can also learn. :-)