I own both a Google Galaxy Nexus (the phone) and a Google Nexus 7 (the tablet). Both of these devices have served me well in the time I had them. Until the Over-the-Air update for Android 4.2 on my Galaxy Nexus. This really ruined my day. Basically the long and short of it is that the battery took a nose dive after installing this update. Immediately I went from a full day of battery life (only charging it while I slept) to approx 3 hours of battery life. As soon as that happened I changed my email checking settings to manual, so that it would not constantly poll, I also disabled wifi, bluetooth etc. However there was a little gem of information in the Battery Usage reports. Basically it was reporting that ~85% of my battery was being used by “Exchange Services” no longer was the screen the biggest consumer of my juice.
After disabling all of these “extra” services my battery report changed a bit, basically Exchange Services went to ~81%. Still flatly unacceptable. Especially considering that this would only give approximately 5 hours of battery time.
Delete your ActiveSync Mail Account, and re-add it. Before you do this make sure you look over your Sync settings so you know what you are Syncing (email, calendars, contacts) so that you can reconfigure your Sync settings appropriately.
Now I am back to once a day charging except on the heaviest of conference call days.