Is it possible to create a web application for WP 8 on JS + Node.js from scratch?

Question

JavaScript

In general, there was a desire to create a mobile web application for WinPhone 8 from scratch. The bottom line is that for WP 8 you can write in JS. So, from JS I know only the basics. There is also such a platform - Node.js, on which you can implement interaction with the database, i.e. use it so you don't have to learn PHP or another server-side language.
Should I keep learning JS to write this application, or should I switch to C# and .NET?

Answer 1

Is it worth continuing to learn JS

Definitely worth it.
This can be used non-backend. But for this, the phone must be connected to the Internet. I would look towards offline. For example use Sqlite on the phone. There is a special JS component that will allow you to make queries to SQLITE.
Node will not work on the phone itself. Just not the server. With it, you can make an API for the application, but this API can be done on something else.

Answer 2

I will add from myself: you cannot create native JS applications on WP8, only WP8.1 and higher supports them.
However, there are frameworks like Apache Cordova and OneCode that allow you to write HTML applications in WP8, they work through the SilverLight layer.