I have worked with android studio for over 2 years and have developed around 6-7 simple UI apps.
I have conducted workshops on Introduction to Android development in 2 Universities.
My most recent app was for a product designing project called Helping Hand (A blind assistance project).

The three parts of the project is on Github, check it out:

Android App - http://github.com/ajsampathk/Blind-Aid-system
WiFi Module Code - http://github.com/ajsampathk/Blind-Aid-Device
EC2 AWS Server code - http://github.com/ajsampathk/Blind-Aid-Server

App release - https://github.com/ajsampathk/Blind-Aid-system/releases