I found that I had a horrible battery drain after turning on the Instant Upload feature in Google+. It first happened on my wife's phone and it indicated Android OS was the problem, so I couldn't figure it out. I then turned the feature on my phone on and my battery started dying quickly showing Android OS as the culprit. I changed the Google+ Instant Upload feature to happen only on Wifi and turned off Battery uploads, problem solved. Now the only issue is when my kids play Netflix and games on battery power for an hour or two, drains the battery fairly quickly.