When the Lumia 920 came out, there were frequent reports of battery life being awful - sometimes lasting less than one hour while idle. I personally had an experience like this - my phone managed to discharge completely while being plugged in once.
This hasn't happened in a very long time, and I suspect it had something to do with Nokia's enhancements or navigation running in the background. As of now, my Lumia makes it through a day without any issue at all - that's with several apps running push notifications and background tasks. I suspect it was some sort of unlisted background task causing problems largely because my phone would be quite hot despite sitting idle.
This hasn't happened in a very long time, and I suspect it had something to do with Nokia's enhancements or navigation running in the background. As of now, my Lumia makes it through a day without any issue at all - that's with several apps running push notifications and background tasks. I suspect it was some sort of unlisted background task causing problems largely because my phone would be quite hot despite sitting idle.