The Android operating system captures over 86% mobile OS market share and a large number of software developers are keen on developing applications for the Android platform. Many Android applications, however, suffer from the problem of slow UI rendering, thereby losing their competitive edge. To be able to address this problem, the developers first need to understand the underlying reasons. In this paper, we present an empirical study on reasons for slow UI rendering on the Android platform, with its focus on the impact of (poor) layout implementation on UI rendering. We also propose a taxonomy of existing techniques that might help tackle the problem and strategies for efficient layout implementation. Results from applying the strategies to sample applications demonstrate that they can help enhance the efficiency of UI rendering.