An arm rehabilitation system for exercising a user's arm. The system provides an arm support device moveable upon a support surface by a user's first arm. The arm support device has a main body configured to movably engage the support surface on one side and has a hand support portion on an opposing side at or toward one end of the body for supporting a user's hand of the first arm. A primary hand support formation protrudes from the hand support portion and a secondary hand support handle extends from the main body at or toward the periphery of the hand support portion. An adjustable switch support boom assembly is also mounted to the main body and has at least one operable user input component for generating an actuation signal in response to operation by the user. An onboard motion tracking system mounted to or within the main body is configured to sense motion of the main body to enable user interaction with an interactive computer system running an application program.