Technicians arranging solar cells to form solar panel on factory production line, South Africa. (carbonbrief.org)
OnePlus» post says, «EngineerMode is a diagnostic tool mainly used for factory production line functionality testing and after sales support. (indianexpress.com)
As OnePlus representative OmegaHsu said, «EngineerMode is a diagnostic tool mainly used for factory production line functionality testing and after sales support.» (slashgear.com)