Sometimes it gets randomly warm and starts draining fast! But even when it doesn't, it does not last very long at all. Maybe around 2 hours I am already at around 50% from a full charge! Anyone else having the same issues? Does anyone have any tips?
I have had the same problem with my Lumia 950XL, check the Settings -> System -> Battery saver, tap on "Battery use". But I notice that in my case the wifi turned on, and the signal switching from 2G-3G-4G causes battery drains and even resets. But it is related with bugs of the OS. The latest version 10.0.10586.107 fixed some of the problems but not all of them. Make sure to update to that version, this is for non insiders.
Keep an eye on this forum to get news about the problem http://answers.microsoft.com/en-us/mobiledevices/forum/mdlumia-mdw10phone/lumia-950-xl-battery-drain-running-hot-and-bizarre/76459887-b579-4cd0-86b1-79ddeacad7cb
I marked the Battery Use answer because it's how I found out what apps make major use of my battery life. My battery life is always something like this:
As you can see, the display takes most of the battery life and this is why I always make sure that brightness is automatically adjusted. Edge is a strange unholy app that takes a big chunk of my battery life too, despite the fact that I set it to never run in the background (Does that even work?). Unfortunately Edge is the best Windows 10 mobile browser out there in terms of displaying content, but if I don't open Edge and turn off my 4G and WiFi, my phone can maybe last for a whole day. Turning off automatic sync with Outlook has improved battery life.
As of now, unfortunately, I need to charge it at least twice a day (a recent update and setting the brightness to 100% but automatically adjusted seems to have made the battery life a little better).