A dual-screen e-reader built by a Reddit user by the name Spacerower folds in the middle like a real book. When opened, it reveals two 5.83-inch e-paper displays. The e-reader is powered by an energy-efficient ESP32S-3 chip and dual 1,300 mAh batteries and can supposedly last more than a month on a single charge. The software though is still in early development; the creator may or may not refine the design and even launch a crowdfunding campaign.https://www.notebookcheck.net/DIY-dual-screen-e-reader-mimics-real-book.1083641.0.html
I can't help thinking that a well designed eReader app on a folding screen phone could do this far more elegantly and naturally...
(Although probably nowhere near as inexpensively...)