Received my 4xl Thursday and decided to give the battery a little test yesterday.
A couple of things. I forced 90hz in developer options, have everything turned on and have brightness on 90.
Normally throughout the day I'm plugging my phone into my car for android auto and when I'm at my desk I can plug in too. I never really have a problem with battery on any phone because I can charge virtually anywhere I am.
So, for yesterday, I didn't plug in anywhere from 6:30AM until 10:30PM.
I used google maps once for 15 minutes, without being plugged in and did some video chatting with my daughter at college for approx. 15 minutes on duo. Otherwise, it was browsing, texting, a little youtube, etc.
At 10:30PM, which was 16 hours unplugged, I was down to 4% battery and I had 5 hours & 28 minutes of SOT.
Again, I forced 90hz, had motion sense and every other feature going too.
I've had a 3xl for a year and I could tell as the day was progressing that my battery was doing better with the 4xl and I didn't really need the stats to tell me that.
The phone is terrific. It's smooth and the display is excellent. I understand the brightness complaints, but I don't have any issue with that.
I'll probably not ever test the battery again like that as I always plug into AA and rarely let my battery go below 50%.
Almost 5 1/2 hours SOT. I think that's quite respectable.