Just for the heck of it, and because I was curious, I wanted to see how long my iPad’s battery would last if I were using it just to read some locally stored Web pages and ebooks in iBooks, Stanza, and eReader.
So I turned off the Wi-Fi and set the brightness just to the left of the middle and started reading.
My fully-charged iPad managed just a shade over 22 hours before it shut itself off. I was astonished.
Apple’s technical specs say that the iPad battery should last “Up to 10 hours of surfing the web on Wi-Fi, watching video, or listening to music.” I note that this ZD net article on iPad battery life cites pleased comments from Pogue and Mossberg and others about the iPad exceeding battery expectations.
I should mention that this is only the second time I’ve ever run my iPad’s battery down all the way, which, by the way, is not what Apple recommends in this iPad battery tech note:
For proper reporting of the battery’s state of charge, be sure to go through at least one charge cycle per month (charging the battery to 100% and then completely running it down).