Connect to pusher in android app, multiple or once?

In my app (streaming series, movies) I have a section for users that can set Reminder for the series or movies. And I implement Pusher to receive server message for reminding data.

Is it true that I connect to channel for each item in the reminder list?? or I should connect to the pusher once and in the pusher event get related series/ movies message?(Server-side implemented pusher for each reminder list items, should we change server-side implementation or I can connect to pusher for each items? )

This is my Implementation for pusher:

 public Pusher getPusher() throws Exception {
        if (pusher == null) {
            HttpAuthorizer auth = new HttpAuthorizer(BuildConfig.PUSHER);
            HashMap<String, String> authHeader = new HashMap<>();
            authHeader.put("Authorization", SharedPref.INSTANCE.read(AUTH_TOKEN, ""));
            auth.setHeaders(authHeader);
            PusherOptions option = new PusherOptions();
            option.setCluster(BuildConfig.PUSHER_CLUSTER);
            option.setAuthorizer(auth);
            pusher = new Pusher(BuildConfig.PUSHER_KEY, option);

        
            pusher.subscribePrivate("private-app_ch." + serialId, new PrivateChannelEventListener() {
                @Override
                public void onAuthenticationFailure(String s, Exception e) {
                    Timber.i("pusher onAuthenticationFailure " + e.getMessage());
                }

                @Override
                public void onSubscriptionSucceeded(String s) {
                    Timber.i("pusher onSubscriptionSucceeded: " + s);
                }

                @Override
                public void onEvent(String s, String s1, String result) {
                    Timber.i("pusher onEvent" + s + ":" + s1);
                    Timber.i("pusher onEvent" + result);

                    
                }
            }, "App\\Events\\AppBroadcastEvent");
        }
        return pusher;
    }

The best practice for this would be to maintain one connection to Channels but make a subscription for each item in the reminder list.

So you would call pusher.subscribePrivate for each item in the reminder list and then on the server side publish to each individual Channel when a reminder needs to be sent.

For example if a user wanted to be reminded about 'Stranger Things' and 'Orange is the new black' you would subscribe to both:

pusher.subscribePrivate("private-app_ch.strangerthings"

and

pusher.subscribePrivate("private-app_ch.orangeisthenewblack"

Your server would then publish reminders about 'Stranger Things' to the Stranger things channel and OISTNB to the OISTNB channel and so on.

This way only relevant updates are sent to the client (server-side filtering). If you only subscribe to one channel the client will get messages they may not want updates about and you would have to filter these out on the client side.

This is also explained here: https://support.pusher.com/hc/en-us/articles/360025398514-Should-i-subscribe-to-lots-of-Channels-

One additional point that is worth considering is that Channels will only maintain an active connection when the app is open. The connection will be closed when the app is backgrounded/closed. This means for reminders to be sent the user would always have to be in your app. You may want to consider also sending push notifications when the app is closed so the user does not miss reminders.