How to start Android development

In the past few years Android development went through on a serious evolution. Nowadays it is easy to start it, there are several websites, video blogs, tutorials and courses, which provides content from beginner to advanced. In this smaller article I collected to you, what is the prerequisites, and requirements to start developing Android applications.
First of all let me introduce a website, which you'll see in the future many times:

https://developer.android.com/index.html

This website is the alpha and omega of all Android developers.

For development, Google changed the primary development tool from Eclipse ADT to Android Studio. You can download it from here:

https://developer.android.com/studio/index.html

Android Studio requires a lot of RAM memory, so if you have a weaker computer, you should upgrade it, or the cheaper solution is to modify some configurations. For this you have to watch the next video:

https://www.youtube.com/watch?v=3TENdS9Qqcc

Next, lets talk about some useful libraries, and what are they for:

• Android Architecture Components (AAC) https://developer.android.com/topic/libraries/architecture/index.html
• Firebase https://firebase.google.com/
• Remote config
• Authentication
• Realtime database
• Analytics
• Crash reporting
• HTTP Clients: They are for sending and retrieving data through the network(local wifi or internet). Currently the best choice from the libraries is the retrofit lib, but Volley is a good one as well. 
• Retrofit2 http://square.github.io/retrofit/
• Volley https://developer.android.com/training/volley/index.html
•  Databases: An Android application has the capability to store data locally on the client user's device. There is the most popular libraries for databases:
• SQLite (RBDMS) https://developer.android.com/training/data-storage/sqlite.html
• Android Architecture Components / Room Persistence Library https://developer.android.com/training/data-storage/room/index.html
• Realm (NoSQL) https://www.realm.io
• Dependency Injection: DI is a great tool in JEE development. With Dagger, we can use this feature in Android development.
• Dagger  http://square.github.io/dagger/
• Data Binding
• ButterKnife (http://jakewharton.github.io/butterknife/)
• Android Architecture Components / Data Binding Library https://developer.android.com/topic/libraries/data-binding/index.html
• Architectural Patterns
• MVP
• Clean Code https://blog.mindorks.com/android-mvp-architecture-extension-with-interactors-and-repositories-bd4b51972339
• Classic https://antonioleiva.com/mvp-android/
•  MVVM https://upday.github.io/blog/model-view-viewmodel/
• MVI http://hannesdorfmann.com/android/model-view-intent
• Testing (https://developer.android.com/training/testing/index.html)

Okay, you have an IDE, let start with some useful resources. In the article intro I mentioned there are countless websites where you can get the necessary informations about how to develop.

Websites:

• https://developer.android.com/index.html (Official Android developer site)
• http://www.vogella.com/tutorials/android.html (Lars Vogel's blog)
• https://medium.com/ (A great website, from intermediate level)
• https://www.tutorialspoint.com/android/ (Tutorials Point)

Youtube channels:

• https://www.youtube.com/channel/UCVHFbqXqoYvEWM1Ddxl0QDg (Android developers)
• https://www.youtube.com/channel/UC_x5XG1OV2P6uZZ5FSM9Ttw (Google developers)

Free course providers:

• https://www.udacity.com/course/new-android-fundamentals--ud851 (Udacity)

I think it's enough to start it! Enjoy :)