And the more apps you install the more likely these added apps will use battery power.
You didn't reveal how old the phone is but at over a year you do see battery runtime drop. And it keeps dropping. At some point you put in a new battery. Before that you factory reset the phone so it's just like new and see how many hours you get.
My phone has recently started acting weired for the last few days.
After charging the phone to 100% its says it will last 47 hours but it only lasts for 10 hours.
At bed time when i turn it to airplane mode and not use it all night, in the morning i find theres only 3% battery left. When i charge it, it now takes 5 hours to even reach 58%.
I cant understand what is wrong with it. I even used battery doctor and antivirus to check if theres something going on and uninstalled all apps in case something is eating away the battery.