We are building a messaging app and we are facing issues with messages delivery.
We are currently using socket.io to send messages on a running app but it's been proven highly unreliable. (Problem with slow network, late timeout, problem when app is in Doze mode,...)
We are thinking about switching to FCM but we have questions regarding reliability and speed. We don't want to change everything to see afterwards that it's not as reliable as wanted.
Have you already used FCM on a production app for every message ? Even when the app is running ?