Got my Note 4 at launch and i easily got over 5 hours screen time when it was new and for quite a bit of the first year. I always charge overnight and unplug in the morning. Then battery got really bad the past few months and lately I struggled to get 3 hours screen time and I had to plug it in during the evening or it would die before i went to bed. I messed with settings and apps and nothing made the battery any better. I finally bought a new Anker battery and i'm on the 2nd full charge and am on pace for about 6 hours screen time. I'm convinced the batteries just do not last like they used to and a year is pushing its lifecycle. If you are having problems I'd suggest just buy a new one. It was $16 so not a whole lot for a years worth.