Small e-ink display for important info
The e-ink display could be used for the outside of a foldable device, so that you can read the time, for example. An e-ink screen uses less power than other screen types, Kuo added in his tweet. He talks about E Ink's Electronic Paper Display (EPD), similar to the screens used in eReaders. This looks like paper and is also easy to read in direct sunlight. It would be very suitable as a second screen on the outside of the device. The image quality doesn't have to be great because you won't be looking at photos on it, but you can read information from widget-like apps.
Apple would like to be the first to release a 9-inch foldable device, which sits between the iPhone and iPad. Initially, Apple will focus on medium-sized devices, Kuo thinks. Then come the bigger screens and finally the smaller ones like the iPhone. Back in February, Bloomberg display expert Ross Young and Mark Gurman both talked about a 20-inch foldable device that sits between the MacBook and the iPad. You can of course not read the screen when folded, and you also do not want to open the screen every time you want to consult the time. An external screen would then be a solution.
Remarkably enough, no e-ink is used in the Android market. The Galaxy Z Flip (see photo) has a small 1.9-inch OLED screen with information about time and notifications. Something like this could also be run as an e-ink screen to extend battery life. With stationary content, such a screen uses no energy and they are refreshed less often, but that need not be a problem with such a screen.
With the Galaxy Z Fold, Samsung takes a very different approach: this device has a 5.2-inch AMOLED display on the outside, similar to a standard phone screen. Inside, you'll find a flexible 7.6-inch main screen.
Whether Apple will actually start working with e-ink remains to be seen. A foldable iPhone is not expected before 2023. Apple's plans may still be shelved in the end, and it's also possible that Apple will conclude that OLED or LCD is a better solution while testing e-ink.