Microsoft recently released Service pack 1 for SharePoint 2013. service pack 1 contain some new features like Office 365 and Yammer integration with SharePoint 2013 Server.
You can now configure Yammer and OneDrive for Business on Office 365 with SharePoint On-Premises integration. This can be done via Central Administration:
OneDrive now replaces SkyDrive in the top link bar. Included with this is Yammer, if you activate the Yammer feature on-premises via Central Administration.
When you click on the Yammer link, you’ll be redirected to /_layouts/15/Yammer.aspx and be asked to log in.
Once Yammer is activated, the SharePoint newsfeed will now display this message when you visit your MySite.
For OneDrive for Business on Office 365 integration, again in Central Administration -> Office 365 -> Configure OneDrive and Sites Link, you’ll simply input your OneDrive host in Office 365 (https://-my.sharepoint.com) and the top link bar will redirect you there when you click on OneDrive.
Happy SharePointing 😉