Backed up my data to Samsung Cloud temporarily, everything except Settings.
Did a factory reset on the phone.
Used the phone as I do normally.
Updated everything including Galaxy Store apps.
Turned off 5G
Turned off Always On Display (AOD)
Turned off AOD when charging
Turned off fingerprint sensor when screen is off.
Only allowed Google and Android System Intelligence on Location permissions. (Allow all the time)
A few days later, after it's learned my usage pattern, it says "a full charge will last about 10 hours." After a few hours, it increased to 10 hours 15 minutes.
I started stopwatch from when the battery has 8 hours, 30 minutes left. Two hours later, I had around 7 hours, 30 minutes left. It drained less than it expected, which is a good thing I guess. Still, 10 hours is probably not enough, and not good enough compared to other people having a whole day as battery life estimates.
Still gotta see for myself later if it continues to improve. At least right now, it's better than it was before I did a reset.
But, just in case that my phone is actually defective, how can I know? I don't trust the diagnostics in this app enough, and I don't trust the technicians on the service centers either. But I'm gonna have to go to them anyway if it really turns out to be a defect.
