The Java Android course is really good.
The Java explanation is also very good, so it is easy to understand and it is a really good course for beginners.

I took the course to learn Android development, and I was able to learn from Java to Android at once,
and I was able to understand Android really quickly. I highly recommend it.!!

qoglacks10296570

You will gain development experience through Java's basic grammar and object-oriented programming, and examples of creating real Android apps. 
This is the first step to Android and is the foundation, so I think you will understand everything if you study it step by step.

survivalcoding

From Java beginners to Android development - Learn Android through developing various apps

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Android

Section 1. Orientation and Configuration

Section 2. Introduction to JAVA 7

Section 3. How to write Java7 programs

Section 4. Expressions and Operators

Section 5. Conditional Branching and Looping

Section 6. Arrays

Section 7. Methods

Section 8. Development using various classes

Section 9. Object-Oriented Programming

Section 10. Instances and Classes

Section 11. Classes

Section 12. Encapsulation

Section 13. Inheritance

Section 14. Abstract Classes and Interfaces

Section 15. Polymorphism

Section 16. Java Standard Classes

Section 17. Exceptions

Section 18. Things You Can Do with Java

Android Development Orientation

Section 19. Creating a Student Management App

How to view official documentation

Section 20. Creating a Membership Form

Section 21. Layout

Section 22. Building an Android Web Browser

Section 23. Creating a Stopwatch App

Section 24. Banking-related apps