https://wccftech.com/galaxy-z-flips-flex-mode-will-be-available-to-other-oems-soon/

While the Galaxy Z Flip might not offer much in the way of raw hardware performance, it does ship with a rather interesting, never-before-seen feature. Upon folding the screen, the phone's UI essentially splits into two halves, allowing you to control one half with the other. The feature is called Flex mode, and it was developed in tandem with Google. A Google spokesperson has told The Verge that it will be available to other OEMs in the near future.

Samsung Galaxy Z Flip Now Official: Features, Specs, Price, Release Date