The exponentially increasing demand for smartphones, tablets, and laptops has made the mobile communication sector one of the fastest-growing industries. Although features and functionality of these devices have improved with time, they still lack in competencies such as processing capability and memory storage, compared to personal desktop computers. Advancements in storage capabilities and infrastructure in cloud-based technologies could be beneficially used to overcome the limitations of mobile devices. This dissertation analyzes the performance and energy consumption of mobile devices used under a cloud-based computing paradigm. This kind of client-server setup enables flexibility in the execution of applications either on the client end or the cloud server end based on the availability of resources at each end. This dissertation analyzes the theoretical limits and proposes optimal methods for energy-efficient application management in mobile devices. Furthermore, in this dissertation, the impact on user experience owing to cloud-based applications is considered and quantified by proposing a user-experience metric, namely "AppScore", a comparison metric that evaluates the relative functionality and performance of applications. Finally, the environmental challenge posed by these mobile devices due to shorter life span is also considered. A comprehensive life-cycle energy (LCE) consumption model for mobile devices is proposed and validated by implementing it on a cloud-based, thin-client (simplified device with fewer hardware components) scenario.