My less than 2 months young LG G2 battery drains very fast. 90% battery level before 12 midnight, 35% remained at 8 o'clock in the morning. I only received 15 Whatsapp text without graphic or video over night. What makes the battery drained from 90% to 35% while I was sleeping ? Do I need to turn off some built-in features that are battery hungry ? Does it matter I keep my phone on 24 hours or should I turn it off during the night ?