To 'diff' an analysis model with a production model as a form of QA/QC, I recommend using grasshopper with the BHoM library
The BHoM library will allow you to database the elements of your respective models (as well as grid locations) and grasshopper components can be used to perform the...
I recommend the easycanvas app for ipads. This allows me to mirror the computer display to my ipad and with an apple pen+bluebeam, I can sketch and create calculations by hand with all of functionality of bluebeam (i.e. hold shift for straight lines)
