Push notification to phone from website?

Question

Mobile development

A form is filled out on the client's website. How to send a push notification to the client on the phone about this? It is necessary to put the application on the phone in advance, I suppose. Then when the form is filled out, a notification goes to the web server, and the web server already understands whose it is and sends it to the client? Generally speaking, is it? And where to read more about how to send from the web server to the application?

Answer 1

And where to read more about how to send from the web server to the application?

This is written in the documentation of apple, google, Microsoft.
In general, it looks like this:
1. The user installs the application on the phone.
2. When launched, the application sends the ID of the channel to which the notification will be sent.
3. During the interaction of the application with the server, the server decides whether to send notifications to a specific device or to all devices with the application installed