The advent of the smart phone as a highly complex technology has been accompanied by mobile operating systems (OS), large communities of developers, diverse content providers, and increasingly complex networks, jointly forming digital infrastructures. The multi-faceted and relational character of such digital infrastructures raises issues around how change and control can be conceptualized and understood. We discuss how change and control are paradoxically related in digital infrastructures and how they affect the evolution of such infrastructures. We examine these paradoxes by examining the change in, and competition between, two mobile operating systems: Apple's iOS and Google's Android along with their related platform features and ecologies. We seek to validate a proposed theoretical framework of the dynamics of change and control through second-order analysis of the two cases. We observe that multiple factors had a significant effect on the evolution of these platforms including user interface, development platforms, business models, and value extraction principles. We observe how these factors significantly affect the evolution of mobile platform ecologies as well as speculate about the future of mobile system platforms.