AWS Certified Developer Associate (#71)

A social media company is using Amazon Cognito in order to synchronize profiles across different mobile devices, to enable end users to have a seamless experience. Which of the following configurations can be used to silently notify users whenever an update is available on all other devices?

Modify the user pool to include all the devices which keep them in sync.
Use the SyncCallback interface to receive notifications on the application.
Use an Amazon Cognito stream to analyze the data and push the notifications.
Use the push synchronization feature with the appropriate IAM role.