A tech blog claims to have dug up a number of Japanese-language patents, awarded to Sharp, that show this OEM's plans for its oneday line of foldable electronics. Some show rather slim-line devices that are most likely clam-shell phones, whereas others appear to be collapsible, mobile gaming machines. One may also be designed to process credit-card transactions.
https://www.notebookcheck.net/Sharp-s-foldable-ambitions-may-extend-beyond-phones-to-smart-bands-and-even-hand-held-consoles.440551.0.html
One sometimes forgets Sharp still does have some operations left in Japan, despite all their phones resembling Chinese ODM.