Yes you're right, when i say "Ipad Pro", I especially want to say IPad Os in fact. This also includes the iPad air since version 2. Anyway, since the arrival of the ARM architecture on mac with the M1, I think it would be much easier to port Simplify3d on Ipad than before. I hope that version 5 of simplify3d, if it ever arrives, will be M1 compatible. Otherwise one day or another we will no longer be able to open the application (like PowerPC and Intel several years ago).
If this new version ever comes out, I really hope that an Ipad Os version will come.
Another interesting alternative would be a web version of Simplify. With a web version, we could use Simplify3d with anything! I think it would be very interesting. And that would fix some issues, especially related to the compatibility run to the latest system ... Simplify3d is not known for its regular updates
. So this could prevent us from being afraid with each system evolution.