The battery level your phone shows is just made-up bullshit. It’s roughly accurate of course, but they can’t really check how much charge is in the battery with 1:100 accuracy, so it just counts down at a roughly constant rate making adjustments to the rate based on rough measurements of broadly whether the battery is “real full” or “mostly full” or “almost empty” or whatever.

The battery has a capacity reading down to the milivolts and the phone knows how much power it is using, which changes dynamically to meet the usage. The remaining battery level is determined by the voltage available at the current consumption. There is some averaging involved based on your usage profile.

So your battery level is accurate at a given time, but changes based on what you are doing and what you have running. So your battery will drain faster if you are playing an intensive game, but will last far longer if you have nothing unessential running and the screen is in sleep mode.

Apps like Facebook, chew through battery in the background because of how often it has to use resources to check for notifications, when when you don’t actually have the app open or in the recent apps list. So your battery will lose charge faster than you would expect when you haven’t been on your phone.

so, naw lil bro.

The remaining battery level is determined by the voltage available at the current consumption

Gets all condescending about how it works

Isn’t aware of the difference between V and mAh or the extremely horizontal (for most of the range) curve defining the relationship between them for Li-ion batteries

I got irritated enough by people spouting off at me to look up how it actually works, it’s not at all how you are describing, although describing it as “bullshit” is probably a stretch

So naw big bro