30-11-13, 01:34 PM
Check in the settings, there's a utility tells you what's using the battery. Mate of mine has a Nexus 5 (which had kitkat out of the box), battery wasn't lasting - the PayPal app was the guilty party. Took it off, no more bother. Both my Nexus 4 and Nexus 7 have been updated, with no change to battery life - it'll be an app you've got that's doing the damage - take it off until it gets updated to fix the issue.