iphone battery depletion

What are the top 5 battery suckers on my iphone 4S???
I run 2 mail accounts, one is an exchange server off my work server. I imagine this tanks a fair bit of battery? There are no notifications on it.

1) Extra bright backlight
2) Turning the phone one and off constantly
3) Running graphic intensive applications (games usually)
4) Watching videos
5) ...

Anything that has push notification enabled will cause the screen to come on for a short time and go off. Doing this repeatedly will consume battery life..

Do you leave Bluetooth turned on all the time even if you're not using it?

Review your push notifications and turn off the ones that don't need to be push.

As Ashwin suggests turn the brightness down to about 50% and turn on auto-brightness detection.

Remember that keeping the Maps app open in the background its still locating your position.

And yes, that Exchange connection (particularly if its set to check all the time) is probably not helping.