A new entry into the United States Patent and Trademark Office (USPTO) may show where Samsung may think foldable displays and their use in the future are headed. It depicts an electronic product that can lay flat, but can also be folded...into a 3D rectangle. This "display device", therefore, may be a new kind of convertible, although it does not really seem that portable.
https://www.notebookcheck.net/Samsung-patents-a-display-that-can-fold-into-a-brick.420447.0.html