A simple app made to learn Firebase along with local data storage for Android

• Description

This is a simple Android log-in/log-out/register app, made to learn:

• Local data storage using SharedPreferences for primitives. This is used to store short messages to be shared between activities such as Toast messages.
• Local data storage using the Room persistence library for structured data using SQLite. This is used to store all the user's data locally for authentication...which probably won't be very secure, so a future implementation should probably conduct authentication and store only the authenticated user's data.
• Cloud data storage using Firebase Realtime Database.