Build Your First App - a tutorial from Google, the creators of Android
https://developer.android.com/training/basics/firstapp/index.html?hl=pLearn Android Basics (Get Started with your First Android App) from Adobe
https://www.adobeknowhow.com/courselanding/learn-basics-android-one-hourFree Android Development Courses from udemy.com
https://www.udemy.com/topic/android-development/?price=price-freeAndroid Development For Absolute Beginners - Youtube Video Tutorials Series
https://www.youtube.com/playlist?list=PLB03EA9545DD188C3Getting started with Android development - Tutorial from Vogella
http://www.vogella.com/tutorials/Android/article.html
YouTube and developer.android.com are indeed the best resources for learning android app development, and there are many android app development specialist who actually utilize these resources for their learning.