Amazon SNS vs Google Cloud Messaging: What are the differences?

Amazon SNS: Fully managed push messaging service. Amazon Simple Notification Service makes it simple and cost-effective to push to mobile devices such as iPhone, iPad, Android, Kindle Fire, and internet connected smart devices, as well as pushing to other distributed services. Besides pushing cloud notifications directly to mobile devices, SNS can also deliver notifications by SMS text message or email, to Simple Queue Service (SQS) queues, or to any HTTP endpoint; Google Cloud Messaging: Simple and reliable messaging to reach over a billion devices. Google Cloud Messaging (GCM) is a free service that enables developers to send messages between servers and client apps. This includes downstream messages from servers to client apps, and upstream messages from client apps to servers.

Amazon SNS and Google Cloud Messaging can be categorized as "Mobile Push Messaging" tools.

Some of the features offered by Amazon SNS are:

• In most cases, developers can get started with Amazon SNS by using just three APIs: CreateTopic, Subscribe, and Publish. Additional APIs are available, which provide more advanced functionality.
• With SNS you can publish a message once, and deliver it one or more times. So you can choose to direct unique messages to individual Apple, Google or Amazon devices, or broadcast deliveries to many mobile devices with a single publish request.
• SNS allows you to group multiple recipients using topics. A topic is an “access point” for allowing recipients to dynamically subscribe for identical copies of the same notification. One topic can support deliveries to multiple endpoint types -- for example, you can group together iOS, Android and SMS recipients. When you publish once to a topic, SNS delivers appropriately formatted copies of your message to each subscriber.

On the other hand, Google Cloud Messaging provides the following key features:

• Versatile Messaging Targets: Distribute messages to your client app in any of three ways — to single devices, to groups of devices, or to devices subscribed to topics.
• Downstream Messaging: For purposes such as alerting users, chat messaging or kicking off background processing before the user opens the client app, GCM provides a reliable and battery-efficient connection between your server and devices.
• Upstream Messaging: Send acknowledgments, chats, and other messages from devices back to your server over GCM’s reliable and battery-efficient connection channel.

According to the StackShare community, Amazon SNS has a broader approval, being mentioned in 230 company stacks & 78 developers stacks; compared to Google Cloud Messaging, which is listed in 18 company stacks and 8 developer stacks.