Adobe have recently released the Creative Cloud 2015 update, making speed and feature improvements to many of their key apps. If you have a CC subscription, there are plenty of new features worth checking out, though not all of them are quite finished yet. One important note, though, is that the default installation option now deletes older versions of the apps rather than leaving them there alongside the new ones.
I actually don’t have a problem with this, because for most apps the improvements are welcome and the files made by newer versions are compatible with the older ones. However, InDesign changes the .indd format with every major release. If you don’t keep older InDesign apps around, then collaboration with anyone who hasn’t upgraded yet becomes a dance involving .idml interchange files.
If you upgrade, but forget to untick the right box under “Advanced Options”, you can still download the older version of the app, but it can take time and will be a large download.