I’d suggest Firebase for scenarios that need real-time notification all way to a device, app, or browser.
Google Cloud Pub/Sub is better aligned to server-to-server messaging, similar to other Cloud queuing services, service buses, event logs, or open-source systems such as RabbitMQ or Kafka.
The scariest/most exhilirating challenge is one he plucked right from the running monologue in my head: "is our company vision really the path to a brave new world, or just a delusion?" http://bit.ly/bdS0
Google Cloud Pub/Sub is better aligned to server-to-server messaging, similar to other Cloud queuing services, service buses, event logs, or open-source systems such as RabbitMQ or Kafka.