Android Basics: User Interface (completed Sat 24 Feb 2018) – https://classroom.udacity.com/courses/ud834
Android Basics: User Input (completed Mon 2nd April 2018) https://classroom.udacity.com/courses/ud836
Android Basics: Multiscreen Apps (started Mon 2nd April 2018) https://classroom.udacity.com/courses/ud839
Android Basics: Networking – https://classroom.udacity.com/courses/ud843
Android Basics: Data Storage – https://classroom.udacity.com/courses/ud845
Developing Android Apps – https://classroom.udacity.com/courses/ud851
Advanced Android App Development – https://classroom.udacity.com/courses/ud855
Then the Big Nerd Ranch textbook course.
There are many more Android Development courses at Udacity which I will take after completing the Big Nerd Ranch textbook course.