[Littlemaster]

i used sketchware before i learned android studio . it is easy and it uses scratch-like coding . unfortunately when i use sketchware i didnt see any volley or something like that . if it is true the only way to access http is to use the webview . for login and register you can use php script and connecting it to a database and with webview you basically convert a website to an app (but with no advantage of  being an app)

Are you using Android Studio in Ubuntu? 
I could not add firebase to my android studio. Let me know if you had success integrating it, and please share the version number.