Microsoft provide the newest Cumulative Update (6) for Microsoft Dynamics NAV 2013 R2. There are both platform and application updates. You can find some very important improvements. Because of that I recommend to install them very soon.
You can find Platform Hotfixes here and Application Hotfixes here on Partner Source.
If you are not Microsoft Dynamics Partner, I recommend that you contact your Partner before installing these updates, because they may cause interoperability issues with customizations, and third-party products that work with your NAV.
I remind you that the latest released cumulative update includes all previous cumulative updates. Therefore, you should always install the latest cumulative update.