Magic Cap (short for Magic Communicating Applications Platform) is a discontinued object-oriented operating system for PDAs developed by General Magic. Tony Fadell was a contributor to the platform, and Darin Adler was an architect.

Its graphical user interface incorporates a room metaphor, where the user navigates between rooms to perform tasks, such as going to a home office to perform word processing, or to a file room to clean up the system files. Automation is based on mobile agents but not an office assistant.

Several electronic companies came to market with Magic Cap devices, including the Sony Magic Link and the Motorola Envoy, both released in 1994. None of these devices were commercial successes.