I’ve been a Rhino user for a lot of years (starting in 2003 with v.3), and am now using the v.7 WIP, but I don’t consider myself particularly adept – I’m retired now and it is sort of an adjunct activity.
But recently for a project that I’m working on, I have found that it would be immensely helpful for my workflow to be able to rotate the view of an object around the vertical axis of the perspective viewport without changing the CPlane. The iRhino 3D app on my iPad does what I’m looking for marvelously just by swiping horizontally across the screen. It is entirely possible that I am just not familiar enough with the abundance of commands or that I am missing something basic, so if someone could point me in the right direction, I would very much appreciate it. (I’ve never done anything with Grasshopper nor Python.)