How to set up receiving data from the site without a request?

Question

Objective-C

I can not find information about how I should receive server information in a stream or by events on the server.
For example, I need to receive data from the server several times a day and process this data immediately in the application.
The option to receive push notifications, then go into the application to send a rest request and receive a response in the form of json does not seem right to me. How can I make sure that the server immediately sends the necessary json with data and the application receives it in the background (if possible) and processes it?
Thanks for the tips and answers

Answer 1

Try looking at firebase.
Or look at websockets. If I understand you correctly.

Answer 2

Thanks, Websocket is what you need