The most immediately noticeable change in version 5.0 is the aesthetic overhaul. The previous interface, while functional, felt rooted in the early 2010s. The new UI is designed for high-resolution monitors (4K and above), offering crisper icons, a darker mode that is easier on the eyes during long print-preparation sessions, and a customizable layout that allows users to dock windows where they see fit.
If you are upgrading from version 4.x, here is why the 5.0 download is worth it. simplify3d 5.0 download