Smartphones are becoming increasingly energy-hungry to support feature-rich applications, posing a lot of pressure on battery lifetime and making energy consumption a non negligible issue. In particular, DRAM is among the most demanding components in energy consumption. In this paper, we propose DR. Swap, an energy-efficient paging design to reduce energy consumption in smartphones. We adopt emerging energy-efficient non-volatile memory (NVM) and use it as the swap area. Utilizing NVM's byte-addressability, we propose direct read which guarantees zero-copy for read-only pages in the swap area. Experimental results based on the Google Nexus 5 smartphone show that our technique can effectively reduce energy consumption.