First off, I am not sure if it is possible, but I suspect the notorious Handy Light app I downloaded last night is the cause of excessive battery usage on my iPhone 4. Let me briefly explain. Downloaded Handy Light last night which was the first app change on my phone in over a week. Every night I switch my phone to airplane mode to conserve battery (which always uses minimal battery consumption). Prior to going to bed, I used the Handy Light app for a few minutes. However even after switching to airplane mode with over 25% battery life left, I woke up to find my phone completely dead/empty. I have never had an iPhone run down so quickly, especially on airplane mode. Could this perhaps have been caused by the Handy Light app not being killed off completely in my task manager? Again I had not downloaded or used any other apps out of the typical mail/fb/settings/camera. Anyone else had this issue? Should I be concerned my iPhone has a power management problem?