Dynamic power management schemes in mobile devices such as smartphones and tablet PCs enhance battery life at the cost of prolonged user-perceived response time while the response time is a crucial factor for user experience. This paper presents systematic analysis of existing power management schemes adopted in recent smartphones in terms of user-perceived response time and energy consumption. For this analysis, we developed a latency measurement benchmark tool to quantify responsiveness to user inputs and used it with an externally-connected power meter to concurrently measure energy consumption and response latency. The evaluation showed that some existing DVFS schemes can significantly harm the response time. More seriously, the analysis revealed that the processor hotplug technique for multi-core systems may reduce responsiveness even without any gain in energy savings.