A recent post from a leaker reveals that Apple is working on a foldable phone for the future.

Dylandkt mentioned in a post that the Cupertino-based company has made several prototypes of a foldable phone. However, there were alleged concerns on foldable technology and if there would be a demand for it when it comes out.
The leaker suggested that Apple wanted to be sure that the foldable feature isn’t just a fad, and is taking a ‘wait and see’ approach depending on market reception. He said that Apple might release a foldable iPhone with 2023 as the earliest possible date.
Foldable iPhone rumors have been circulating since 2016, and there were several patents submitted by Apple to back the claims. A prototype recently came to light regarding two separate displays attached via a hinge, and another came out with a clamshell-like design.
Samsung and other Android phone companies have already adopted the folding smartphone, albeit with high price tags and durability concerns.