About 15 years ago I was at the home of an engineer. He had something which looked like a wallet. He unfolded it and it was an e-ink screen which was foldable.

About 15 years ago I was at the home of an engineer. He had something which looked like a wallet. He unfolded it and it was an e-ink screen which was foldable. It showed an OS with an app to read and send emails and do some (slow) browsing. The company he worked for was bought by Philips. Never saw that product again.