As an ESD Engineer at Apple, the responsibilities include defining ESD methodologies for all silicon developed, specifying chip and IP level ESD requirements, designing ESD protection devices and circuits, developing test structures for characterization, creating design rules, collaborating with foundries on ESD library and rule development, maintaining an ESD device library, generating/reviewing ESD/LUP testing plans, managing sign-off reviews, and driving ESD/LUP debug activities. This role requires expertise in ESD design and implementation to ensure product reliability and functionality.