Better Battery Life
The iPad battery can last for up to 10 hours, but you can squeak out a bit more usage. Drag the brightness slider (under Settings, Brightness) as low as you can stand, turn off both Wi-Fi and Bluetooth (under Settings), don't play and videos or music, and avoid gaming apps.
Turn off or decrease the timing for data fetching. Data that is updated regularly includes email notifications and RSS feeds.
Turn off Location Services. Active use of maps and other location services will drain battery life. If left on, Maps updates continuously, something that you don't need draining your battery.