Settings > Device > Display.
If you don't need it, turn off automatic syncing for all apps:
Settings > Accounts > Google account-name. This means you
need to sync manually to collect messages, email, and other
recent information, and won't receive notifications when up-
If you know you won't be near a mobile or Wi-Fi network for a
while, switch to Airplane mode: press and hold the Power but-
ton, or go to Settings > Wireless & networks > More > Airplane
Check battery level and usage details
open Settings > Device > Battery.
The list at the bottom of the screen shows the breakdown of bat-
tery usage for individual apps and services. Touch a graph for
more details. The details screen for some apps includes buttons
that allow you to adjust settings affecting power usage, or stop
the app completely.
may not work correctly.
battery status (charging, discharging) and level (as a percentage
of fully charged) are displayed at the top of the screen.
The discharge graph shows battery level over time since you last
charged the device, and how long you've been running on battery
Nexus 7 Guidebook
if you stop some apps or services, your device