mobile – How do I keep users of a PWA up to date when the application is in idle / hibernate?

So I’m currently building a .Net Blazor PWA, and I was wondering how the behaviour of my application looks like when it is installed on a mobile device, and the user is done with the app for the time being.

My current setup looks like this:

The Blazor application builds up a SignalR connection to my server (which is essentially a C# websocket implementation) and will receive notifications if necessary. Notice, that this does not go through the serviceworker. I’m not sure if this is done right by me, since I don’t have much experience with PWA’s yet.

So, this all works fine when the application is running in a normal state. However, I’m wondering what happens when the application would be closed / moved into the background on a mobile operating system (Android or iOS).

I assume that this could cause some troubles. Since I had very little exposure to mobile OS so far, I read up a little, and figured out that apps like Telegram or WhatsApp can continue to use websockets or polling even when idle since it’s a native application, but browser-hosted PWA seem to be cut off.

So, given this information, how can I ensure my PWA users will keep receiving notifications, even if the app is not running?