The mobile push notifications are the most valuable. Previously, we used to use Firebase Cloud Messaging (FCM) for this functionality. It is a Google service for sending push notifications. Android did not have a good service for sending push notifications, but now, Amazon SNS integrates with FCM. Under the road, it is actually using FCM, but we can see all the metrics on our AW service itself, which makes it a lot easier instead of using a third-party service for this particular functionality.