Mobile operating systems differ from desktop operating systems primarily in their architecture and user interface design. Mobile OS focuses on touch-based interactions, optimizing for smaller screens and energy efficiency. They are often built to support app ecosystems where applications are commonly distributed through centralized stores. On the other hand, desktop operating systems prioritize >multi-window functionalities and robust file management systems. Desktop OS typically support a broader range of hardware and software applications compared to their mobile counterparts, which are usually tightly integrated.