My current version of NAV is functioning fine; Do I even need to upgrade to a higher version.

I have been using Microsoft Dynamics NAV 2009 for a few years now. The system works perfectly fine for me. Hence, my question is: do people like me even need to update to NAV 2013 R2? Moreover, I have heard that NAV has released its latest upgrade, Dynamics NAV 2015. Can I upgrade to NAV 2015 directly from NAV 2009, or should I upgrade to NAV 2013 R2 first?

Need to update? Depends on what you want. Here I have customers running on NAV 4 and some even older .

Main reasons for upgrading are usially
*new functionalities
*compiability to other systems(!)
*demands from environment (like OS)

Not quite sure, but I guess that you’ll be able to upgrade from 2009 till 2015 directly, probably via 2013 and 2013r2.