I, like most everyone else, charge my phone over night. While I previously had a different smart phone I read that people think that if you leave your phone on a charger it will stay topped up. Not so. Once the phone is fully charged the charger stops charging the battery. If the phone is on while charging, when the battery reaches full charge the charging stops and the phone starts to discharge slowly. Of course, if the phone is off it should not discharge the battery. I have noticed this on my Bionic which I leave on 24/7. In the morning when I take it off charge it will drop in power rather quickly initially. I then put it back on charge and remove it as soon as it reaches 100%. The charge then does not drop as quickly. Try it and see if you notice this too.