Angular2 AngularFireDatabse giving error when using list() or push() method, are them not supported anymore? [on hold] - firebase

I am trying to save images on Firebase storage, and to retrieve their url from firebase database so i can display.
But db(instance of AngularFireDatabase) methods like list or push are not recognized


firebase response mobile data Usage

I am building an app that uses firebase storage to store userdata.
I am using firebases rest API with the fetch function, to save data on there with the PATCH method.
Now i just realized, that if i always get responses from the database with my data i just added, the user will always download the data he added to the app and use up his mobile data volume.
Is there any way to make firebase not send ALL the data i just saved on the database and instead just send a response with a confirmation that everything went well?

Firebase check for new data on app load

Does firebase have a native way to check if the app has the latest data on the second load?
Here is the app workflow.
When the app loads I get data from firebase and display it to the
Data is also stored locally to be displayed later.
The user closes the app and the reopens it sometime in the future.
How do I check if Firebase had new data and get it only if it has?
What I am doing is that I am storing a TimeStamp on my device and on the database. On each app load I check if the TimeStamp matches.
If it does then I display old local data otherwise make call to get latest.
Is this the correct way?
Basically what I am asking is I want to display locally stored data, but if firebase has new data then I want to get it and display that.

Should I manage database node subscriptions in an Angular/Ionic app using angularfire2?

In an ionic app, say I have several different pages. Let's say I make some database query in each of the different pages where I assign a class variable to the result of the db query. Like so:
bills: Observable<any[]>;
this.bills = db.list(this.constants.BILLS_ROOT_NODE, ref =>
Should I be unsubscribing or managing these subscriptions somehow? Does each subscription die once I navigate to a new page? What happens if two different pages end up requesting a similar node, should that be pulled out into a provider and then injected? Should all of my database calls be pulled out into a provider?

Connecting Firebase to Unity for simple Log In

I am trying to create a simple log in using unity, I have connected it to firebase but not sure how to populate the database in firebase? I have created a simple GUI but need to link it to firebase so every time I enter text it can populate the database?

How can I upload a video to Firebase using angularfire2?

I am building a web app using Angular2 and Firebase, and am using angularfire2 for authentication and database interactions. It seems like angularfire2 does not have support for the Firebase storage API yet.
What is the alternative until then?
Can I access the Firebase object and follow the instructions in the Firebase documentation?
just use the firebase object and follow the directions on website
I use different approach by
create static html+js for the sake of upload only
make angular2 make a popup of upload page then when it complete upload close it self + change state of localStorage
use ngZone + window.addEventListener("storage") to be able to call back after uploading is done
here is other ppl example to use ngZone