If you find your iOS device low on juice more than you think it should be, it may not be the fault of Apple. Many app makers have default settings that require your device to constantly contact the network, call home, or push notifications to you.
You didn’t set it up that way, but some apps require you to affirmatively turn those settings off. Here’s how to check to see if some of your apps are burning juice unnecessarily.
Mail, Contacts, Calendars
If your iPad is constantly checking your mail, even when you are not, that can be a source of battery drain. To modify the behavior, tap Settings > Mail, Contacts, Calendars.
Then you can turn off push notifications and check your mail manually by opening the Mail app, tapping on a mailbox and then at the bottom left, tap on the rounded arrow. Doing so will refresh (recheck) your mail.
Apps
To check what individual apps are doing, tap settings and scroll down the left side until you see Apps and a list of apps. Tap on each app to see what the various settings are.
For example, Facebook seems to turn on every juice sucking setting by default. If you don’t want to know every time a friend posts something to Facebook or don’t want an alert every time there is a wall post, slide the Push notifications to “OFF” by sliding the ON to the left.
Tap on each app to see if there are unnecessary or unwanted push notifications or similar tasks being performed in the background that you are simply not interested in having updated every few minutes.
Conclusion
If there are background tasks running that you are not interested in, turning them off can save your battery and unnecessary pop up notifications.