The silicon that chips are etched into is rigid and so is the glass substrate for a display – so how can you fold a phone without breaking it? To answer that we have to start at the beginning, which in our case is late 2013. The Samsung Galaxy Round launched on October 10 in South Korea (exclusively on SK Telecom) and became the first commercially-available smartphone with a flexible AMOLED display. The whole phone was curved (side to side), which made a ton of sense if you think about it. Your thumb moves in an arc and when you put the phone in your pocket, a curved device will conform...
Source: https://www.gsmarena.com/flashback_the_samsung_and_lg_phones_that_learned_to_flex_so_that_future_models_can_fold-news-50606.php
