I use Cortana rarely and the location is turned on only when I'm using it...
So I'm not sure why the battery is so terrible :/
I had to charge my phone twice yesterday, which never ever happened!
Over the past week my battery is getting worse and battery sense says ie is using the most battery. Today I was using Netflix and I had over half battery lift and in 55min the battery was dead. I find it very speratic. I would turn off the phone and when I turn it back on it would say I have more battery then before I turned it off. Hopefully when the official release comes it will fix the battery.
When near to known wifi networks the wifi button on the action center shows the text "AVAILABLE" but it doesn't connects until some minutes have passed (or when you enter to the wifi settings), this didn't use to happen on the previous 8.1 release.
And I noticed that my calendar tile stopped working, it displays only the calendar icon, this happened after resizing the tile from medium to big.