No root needed for app ops, its not really an app, more of a shortcut to the feature which Google don't want to make official yet. But it's a part of android and with 4.4 they have included the ability to disable keep awake for almost every app. It does wonders for battery life. I got 3,5 days with 11 hours screen on time. The development of android has become too fragmented so there's no consistency any longer, that's why most battery drainage nowadays is caused by Google's own apps. And if you disable keep awake for eg Facebook messenger you will still get notifications, even if the tablet is in deep sleep. So i honestly don't understand what the keep awake function is for. I have disabled it for all apps, Google services, Google play store + the sub stores like play books, games etc and android system. I haven't had any problems.
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