I believe I solved the 8.1 battery issue. Please read.

[AgentWhiteBread]

Chezm, you need to share your iPhone settings with my mom! She has a portable charger, 2 car chargers, and several wall chargers around the house because her phone dies alllll the time.

 

[hairychad]

AgentWhiteBread, my phone is at 23% when I normally feel it dying about 3 hours earlier than this... It did do earlier with a short usage of nextgen reader, so I may switch to a different client... It dropped 10% in 2 minutes..,
Anyway, digression aside... Thank you for your "science" as it has gotten me further in the day

 

[Michael Dzikowski]

Is there any real fix for this?

I am getting awful battery performance on my Lumia Icon running 8.1 with Dev Preview.

I've seen this thing chew through 100% battery to 20% remaining in 4 hours.

I've also seen my phone go from 50% charge, to 10% critically low while running GPS , on a 30 minute drive (phone ended up being super hot while GPS was running).

I dont know if I should purchase a different phone or if I should try to revert to 8.0. It seems that these issues started happening after the 8.1 upgrade.

Things I've tried:
Factory Reset
Updated to latest firmware
Removing any applications that might be consuming battery
Turning battery saver on always (which seems to hurt the battery life actually)
Using WiFi instead of LTE/4G when WiFi is available
Made sure all of my accounts were syncing properly and no passwords were incorrect

If anyone has a "real fix" for this, I'm all ears. We shouldn't have to disable every feature of this phone in order to have the battery last more than 4-6 hours.