NodeJs for real-time applications

Recently, with the arrival of Angular2 beta, I have been looking for more information regarding real-time applications.

I currently work with AngularJs (1.x) on front-end with apache server on MySql & Php to backend , which is not easy for this type of application.

I found some materials and have done some basic testing projects using Angular2 and Firebase . But Firebase , although excellent and simplify work, ENOUGH does not meet the need when I need something more structured and elaborated, such as an e-commerce, customer portfolio, etc. ..

Reading more about this, or more specifically MEAN, I find the proposal to use this set very interesting. But before deciding to switch to one or the other, I would like to understand more about this scenario.

Unlike Firebase , which already has automated client-server communications functions, if you use a server in NodeJs you would need to use some WebSocket tool, such as socketo.io , so I would like to ask you some questions:

• When using my application with Angular2 on front-end and NodeJs backend, what would be a good database to use together? MySql or MongoDb are the strongest options I have right now. The first one for being the one that currently work and the second for seeming similar and already be together with the model MEAN. But if there is another better option, it will be welcome as well. The only request is to have a good performance in real-time app.

• If I choose to use NodeJs do I need to use any specific hosting? Or the most common ones that exist in the market today already supply? Like the hosting Uol, Weblink (currently used), Locaweb, etc ..

If you have more comments about the subject, please comment, because I am in this impasse of change of backend language and would like to know more before making the decision. Thank you.