This app is always under development. It is just a list of some things that I have worked with Android, experimenting, and testing.
http://www.nickagas.com/

MvvM with RxJava, Room, Timber
JobScheduller
Firebase
FCM
FireBaseUI
TabLaout
TabLaayout2 with bottom View Navigation
ParseServer
Glide
ButterKnife
auto restart app
Event Bus
Notification
SQLite CRUD
Kotlin login and register with PHP Authentication on the backend