According apple.com:

• Up to 10 hours of surfing the web on Wi-Fi, watching video, or listening to music
• Up to 9 hours of surfing the web using 3G data network

I'm using my iPad2 for some time and I think my battery drains a bit faster.
So I'm just wondering what that 9-10hrs really mean.

What if my iPad goes to sleep mode with tens of applications opened and no active data connection?

What if my iPad goes to sleep mode with imo.im or other network using app opened? Does the time in sleep with active data connection counts towards 9-10hrs?

How could I be sure that my iPad really last 9-10hrs? Just open one browser tab and surf the web non stop without opening any other application and without turning off to sleep?

Thanks!

Lower the screen brightness just a little will help extend battery life a lot

i think the 9-10 hour stated is a pretty best scenario optimised time? not the 'norm' maybe?

i've never timed mine. i'm sure its nowhere near 9-10 hours. i'll try it out real soon i think. all i do all day is stay logged into skype and internet via wifi. nothing amounting to any great power drain me thinks.

Originally Posted by Rudinater

Lower the screen brightness just a little will help extend battery life a lot

Thanks.
But that was not an answer to my question I'm aware of what saves battery (like location services, notifications, etc.).

The questions is: does the sleep mode counts towards theoretical maximum of 9-10hrs if iPad is in sleep mode (with active network connection and many apps opened and with many apps opened but no data connection).

What are you worried about? Do you believe that you aren't getting full battery life? There are many ways that people tested the iPad battery.
iPad battery life test - Google Search
There are also several battery apps that will tell you how much times left.
ipad battery app - Google Search

IMHO - what it means is I can take my iPad with me, use it all day, and not have to worry about charging it.

Specifically your question, depending on the backgrounding, a program may drain the battery while sleeping. I've found the worst offenders are location apps and the push/fetch mail apps. Even with that, and my iPad sleeping some of the day, I find i don't have to charge until night time. I don't really have to close apps.

Also, playing galaxy on fire 2 - a 3d game, I can play for hours at a time before having to charge. I could probably play 6 hours before hitting 20%.

The point is, the iPad bettery lasts forever. It is good to drain it down every now and then. (battery calibration).
Apple - Batteries - iPad
If you are truly worried about data use,turn on airplane mode until you need to use data.

Originally Posted by sjleworthy

i think the 9-10 hour stated is a pretty best scenario optimised time? not the 'norm' maybe?

i've never timed mine. i'm sure its nowhere near 9-10 hours. i'll try it out real soon i think. all i do all day is stay logged into skype and internet via wifi. nothing amounting to any great power drain me thinks.

Thanks!
Would be nice to see the results of whatever test case.

Originally Posted by bullka

Originally Posted by rudinater

lower the screen brightness just a little will help extend battery life a lot

thanks.
But that was not an answer to my question i'm aware of what saves battery (like location services, notifications, etc.).

The questions is: does the sleep mode counts towards theoretical maximum of 9-10hrs if ipad is in sleep mode (with active network connection and many apps opens and with many apps opened but no data connection).

no:d

My first charge lasted 4-days under light/casual use. For more active periods or extended travel I have the New Trent Power Pack, which is designed to provide a full recharge. I'll see how it goes during an upcoming international travel trip.

Originally Posted by IvanLasston

It is good to drain it down every now and then. (battery calibration).

While that was the case with older Ni-cad battery's that is not the case with Li-Ion or Li-Po battery's.

With Li-Ion and Li-Po battery's they are good for about 1000, charges/discharges cycles. Draining the battery for just the sake of draining and recharging it does nothing but use one of those 1000 cycles.

the 9-10 hour battery life is for constant 'on' use. switching it into semi off or sleep mode will give you a whole lot more. again, as long as there aren't apps running in memory in the background.

i know with mine from a full charge and nothing on in the background, i get a good couple of days standby time.