Google cloud messaging: register_id against device group

Question

When do I prefer to send a message to a group by the list of registration identifiers ( message with the registration_ids parameter )?

It seems that managing device groups only complicates. For a group of devices, the application server must contain the logic for creating the group or simply add a registration identifier. The server still needs to save the registration identifiers in some database and, in addition, now it needs to save the notification key. the answers look less detailed: the reason for the failures is not indicated, so it’s harder to know what needs to be done to prevent the failure (was the application deleted? Is the registration token valid, etc.).
What am I missing? What are the benefits?

Thanks in advance!

Answer 1

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Answer 2

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