i have the smart cover Tim,does that turn it off or just put it to sleep?So you're not getting the 10 hours?
There are no app's but plenty you can do...
Do you ever run the battery right done to zero? You need to do that occasionally to let the iPad battery monitor calibrate itself, else it tends to report erroneous battery levels.
Keep the LCD brightness down.
Turn off 3G or WiFi if you're not using them.
When the iPad is not in use for a while turn off rather than putting it to sleep.
Tim