Abstract: Ergonomic chairs, systems and hand and arm support structures capable of comfortably supporting upper arms, forearms, back, seat, and hand heels of a user are provided. Devices and device holders designed for ergonomic benefit to be utilized in conjunction with the chairs, systems, and support structures are also disclosed. Device holders feature a platform and a hand heel rest. Actuator components of a number of the devices are disposed on a multidimensionally arcuate surface.