Dark and Darker Mobile is planning to make constant efforts to optimize the game to make a pleasant environment on various hardward/mobile devices.
To make your device get less heated and use less battery, please select 'Low graphic quality' and set maximum FPS at 30 in the in-game setting. By selecting lower options in display settings, you can reduce the overheating and battery drain of your device.
However, please note that your battery consumption rate may differ depending on your mobile device and environment.