Which is the best place to learn Android app development?

Pursuing the skills of core Java which leads to android development would require 3-4 months. Mastering the same is expected to take 1 to 1.5 years . Thus, in brief, if you are a beginner, it is estimated to take you around two years to have a good understanding and to start with android development projects.

5 Websites to Learn Mobile App Development At your Own Pace