Brightness effects my iPhone 6 by what seems to be an abnormal amount. 100% brightness causes hot phone, probably 4 hours on a charge. 75% is pretty warm, 5 hours at most. 50%, warm, 5.5 at most. 30% even produces warmth and gets 6 hours at most. I have gotten used to running at about 10% and rarely feel any heat and get about 8 hours on a charge. That's with turning cellular off when I don't need it and turning wifi off when I don't need it, same goes for Bluetooth. Not sure how you guys get 9-11 hour cycles at 50% brightness. I could enjoy my phones screen at a higher brightness since I have a ton of chargers around the house too, but I hate feeling heat radiating off of a device. Even the slightest amount of warmth makes my hands get clamy and gross, which then causes Touch ID to not work
Plus when I see the battery going down 20% in 45 minutes and the phone getting hot to the touch from Safari and social media, it concerns me.
OP, how much time do you usually get on a full charge when viewing Settings>General>Usage>Battery Usage? What's your cell service like? What apps are in the list at what percentage? Screenshots at 1%? Does your phone drain a lot in sleepmode, or just abnormally fast for light tasks? Does "Usage" match "Standby"? What's your brightness? Brightness is probably the biggest tip I can give. Next tip is if you're on wifi, turn off cellular data if you have a low signal. Your phone, if connected to wifi and all, is at all times is receiving the networks for texting and calling, cellular networks such as 1x, 3G, 4G, LTE, and WiFi on top of that. Turning off cellular data when I'm on WiFi has helped me a little I believe, I get about -115db of LTE in my house but a strong, consistent WiFi signal. Oh, and this may sound dumb, but if you use Safari a ton and its draining power a ton as well, try not to be so fickle with webpages. Yeah, I know. But I usually would browse and really quickly jump from page to page nonstop and it was causing excessive drains. I now actually stop and read things more and get involved in more threads on here (rather than just hopping from thread to thread and moving on) and as a result, I've noticed a huge increase in battery life. I never could get more than 6.5 hours at 10% brightness but I got 8 and a half hours the other day and I even left home and connected to LTE networks and such (which uses more power). First 60% was on Wifi and the last 40% or so was on cellular networks. Up until the time I left the house I was on track for a 10.5 hour charge.