Tags: Auto sync, GPS high accuracy, and hotword detection
You may disable the automatic sync/backup to Google + or Verizon Cloud or any 3rd party cloud before the kitkat update,But the auto sync /back up feature will turn on after installing Kitkat.
This is why your Battery Drain fast after the kitkat update.
You need to turn off the automatic sync feature after installing the update.
Please allow your handset 24-48 hours to sync data with all your account, or cloud and download the update for some 3rd party apps. You should have more battery life with power saving mode after the automatic sycn process.
The Kitkat uses more location services, after the update, your handset will re-check your GPS position in a high accuracy mode , this drains battery a lot too.
Solution: Go into settings > location and then set location mode to battery saving instead of high accuracy.
Third.: The “OK Google” hotword detection is constantly trying to listen for the hotword, this process drains batter a lot.
Solution: Turn off hotword detection feature:
Google Now – swipe up from home button. When in Google Now, click on menu settings and then Voice and then “OK Google” hotword detection – turn off this feature
The Last, You need to go-settings-battery to monitor battery usage, you can check which apps/process use the battery a lot. In most of cases, The download app use more than 50% of your battery after you install the kitkat update if you have not disable the automatic sync/backup feature.