When to Use Chatter REST API in salesforce?

Hi Piyush,

Use Chatter REST API to:

• Build a mobile app.
• Integrate a third-party web application with Salesforce so it can notify groups of users about events.
• Display a feed on an external system, such as an intranet site, after users are authenticated.
• Make feeds actionable and integrated with third-party sites. For example, an app that posts a Chatter item to Twitter whenever the post includes #tweet hashtag.
• Create simple games that interact with the feed for notifications.
• Creating a custom, branded skin for Chatter for your organization.