I've had my Samsung S7 since they came out (3 years? Longer?). The phone works perfectly, but the battery now drains quickly.....like in half a day, where I used to get 10+ hours without charging. I frequently clear cache, optimize storage, clean junk, kill background apps, and have the power saving mode on "mid". Still drains too quick.
Is it time to just replace the battery, or is this a hardware issue?