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Govt. Certified Facebook Apps Developer

What is Realtime Update?

Realtime update is a Facebook service provide you the capability to subscribe to the changes in the data. For example, you can listen to the changes of user’s Facebook likes. That expands your app’s capability.

How does the Real-Time Updates Work?

The whole work flow of the real-time updates can be explained as follows:

• First of all, you register an subscription for the updates (telling Facebook what pieces of information your application will be monitoring) for your application.
• When a user of your application changes the information that your application has subscribed, Facebook will send a change notification to your application.
• Based on the change notification (which tell you which users and what information they had changed), your application can take the necessary actions.
  For example, your application can query the updated data immediately and update the local cached copy. However, it should be noted there unless you have the offline_access permission granted, some of the data may not be available when the user is not using your application. In such a case, you can probably mark it in the local database so that appropriate actions can be taken when the user returns later.